linux/arch/powerpc/kernel/exceptions-64s.S

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/*
* This file contains the 64-bit "server" PowerPC variant
* of the low level exception handling including exception
* vectors, exception return, part of the slb and stab
* handling and other fixed offset specific things.
*
* This file is meant to be #included from head_64.S due to
* position dependent assembly.
*
* Most of this originates from head_64.S and thus has the same
* copyright history.
*
*/
powerpc: Rework lazy-interrupt handling The current implementation of lazy interrupts handling has some issues that this tries to address. We don't do the various workarounds we need to do when re-enabling interrupts in some cases such as when returning from an interrupt and thus we may still lose or get delayed decrementer or doorbell interrupts. The current scheme also makes it much harder to handle the external "edge" interrupts provided by some BookE processors when using the EPR facility (External Proxy) and the Freescale Hypervisor. Additionally, we tend to keep interrupts hard disabled in a number of cases, such as decrementer interrupts, external interrupts, or when a masked decrementer interrupt is pending. This is sub-optimal. This is an attempt at fixing it all in one go by reworking the way we do the lazy interrupt disabling from the ground up. The base idea is to replace the "hard_enabled" field with a "irq_happened" field in which we store a bit mask of what interrupt occurred while soft-disabled. When re-enabling, either via arch_local_irq_restore() or when returning from an interrupt, we can now decide what to do by testing bits in that field. We then implement replaying of the missed interrupts either by re-using the existing exception frame (in exception exit case) or via the creation of a new one from an assembly trampoline (in the arch_local_irq_enable case). This removes the need to play with the decrementer to try to create fake interrupts, among others. In addition, this adds a few refinements: - We no longer hard disable decrementer interrupts that occur while soft-disabled. We now simply bump the decrementer back to max (on BookS) or leave it stopped (on BookE) and continue with hard interrupts enabled, which means that we'll potentially get better sample quality from performance monitor interrupts. - Timer, decrementer and doorbell interrupts now hard-enable shortly after removing the source of the interrupt, which means they no longer run entirely hard disabled. Again, this will improve perf sample quality. - On Book3E 64-bit, we now make the performance monitor interrupt act as an NMI like Book3S (the necessary C code for that to work appear to already be present in the FSL perf code, notably calling nmi_enter instead of irq_enter). (This also fixes a bug where BookE perfmon interrupts could clobber r14 ... oops) - We could make "masked" decrementer interrupts act as NMIs when doing timer-based perf sampling to improve the sample quality. Signed-off-by-yet: Benjamin Herrenschmidt <benh@kernel.crashing.org> --- v2: - Add hard-enable to decrementer, timer and doorbells - Fix CR clobber in masked irq handling on BookE - Make embedded perf interrupt act as an NMI - Add a PACA_HAPPENED_EE_EDGE for use by FSL if they want to retrigger an interrupt without preventing hard-enable v3: - Fix or vs. ori bug on Book3E - Fix enabling of interrupts for some exceptions on Book3E v4: - Fix resend of doorbells on return from interrupt on Book3E v5: - Rebased on top of my latest series, which involves some significant rework of some aspects of the patch. v6: - 32-bit compile fix - more compile fixes with various .config combos - factor out the asm code to soft-disable interrupts - remove the C wrapper around preempt_schedule_irq v7: - Fix a bug with hard irq state tracking on native power7
2012-03-06 15:27:59 +08:00
#include <asm/hw_irq.h>
#include <asm/exception-64s.h>
#include <asm/ptrace.h>
/*
* We layout physical memory as follows:
* 0x0000 - 0x00ff : Secondary processor spin code
* 0x0100 - 0x17ff : pSeries Interrupt prologs
* 0x1800 - 0x4000 : interrupt support common interrupt prologs
* 0x4000 - 0x5fff : pSeries interrupts with IR=1,DR=1
* 0x6000 - 0x6fff : more interrupt support including for IR=1,DR=1
* 0x7000 - 0x7fff : FWNMI data area
* 0x8000 - 0x8fff : Initial (CPU0) segment table
* 0x9000 - : Early init and support code
*/
/* Syscall routine is used twice, in reloc-off and reloc-on paths */
#define SYSCALL_PSERIES_1 \
BEGIN_FTR_SECTION \
cmpdi r0,0x1ebe ; \
beq- 1f ; \
END_FTR_SECTION_IFSET(CPU_FTR_REAL_LE) \
mr r9,r13 ; \
GET_PACA(r13) ; \
mfspr r11,SPRN_SRR0 ; \
0:
#define SYSCALL_PSERIES_2_RFID \
mfspr r12,SPRN_SRR1 ; \
ld r10,PACAKBASE(r13) ; \
LOAD_HANDLER(r10, system_call_entry) ; \
mtspr SPRN_SRR0,r10 ; \
ld r10,PACAKMSR(r13) ; \
mtspr SPRN_SRR1,r10 ; \
rfid ; \
b . ; /* prevent speculative execution */
#define SYSCALL_PSERIES_3 \
/* Fast LE/BE switch system call */ \
1: mfspr r12,SPRN_SRR1 ; \
xori r12,r12,MSR_LE ; \
mtspr SPRN_SRR1,r12 ; \
rfid ; /* return to userspace */ \
b . ; /* prevent speculative execution */
#if defined(CONFIG_RELOCATABLE)
/*
* We can't branch directly; in the direct case we use LR
* and system_call_entry restores LR. (We thus need to move
* LR to r10 in the RFID case too.)
*/
#define SYSCALL_PSERIES_2_DIRECT \
mflr r10 ; \
ld r12,PACAKBASE(r13) ; \
LOAD_HANDLER(r12, system_call_entry_direct) ; \
mtctr r12 ; \
mfspr r12,SPRN_SRR1 ; \
/* Re-use of r13... No spare regs to do this */ \
li r13,MSR_RI ; \
mtmsrd r13,1 ; \
GET_PACA(r13) ; /* get r13 back */ \
bctr ;
#else
/* We can branch directly */
#define SYSCALL_PSERIES_2_DIRECT \
mfspr r12,SPRN_SRR1 ; \
li r10,MSR_RI ; \
mtmsrd r10,1 ; /* Set RI (EE=0) */ \
b system_call_entry_direct ;
#endif
/*
* This is the start of the interrupt handlers for pSeries
* This code runs with relocation off.
* Code from here to __end_interrupts gets copied down to real
* address 0x100 when we are running a relocatable kernel.
* Therefore any relative branches in this section must only
* branch to labels in this section.
*/
. = 0x100
.globl __start_interrupts
__start_interrupts:
.globl system_reset_pSeries;
system_reset_pSeries:
HMT_MEDIUM_PPR_DISCARD
SET_SCRATCH0(r13)
#ifdef CONFIG_PPC_P7_NAP
BEGIN_FTR_SECTION
/* Running native on arch 2.06 or later, check if we are
* waking up from nap. We only handle no state loss and
* supervisor state loss. We do -not- handle hypervisor
* state loss at this time.
*/
mfspr r13,SPRN_SRR1
KVM: PPC: Allow book3s_hv guests to use SMT processor modes This lifts the restriction that book3s_hv guests can only run one hardware thread per core, and allows them to use up to 4 threads per core on POWER7. The host still has to run single-threaded. This capability is advertised to qemu through a new KVM_CAP_PPC_SMT capability. The return value of the ioctl querying this capability is the number of vcpus per virtual CPU core (vcore), currently 4. To use this, the host kernel should be booted with all threads active, and then all the secondary threads should be offlined. This will put the secondary threads into nap mode. KVM will then wake them from nap mode and use them for running guest code (while they are still offline). To wake the secondary threads, we send them an IPI using a new xics_wake_cpu() function, implemented in arch/powerpc/sysdev/xics/icp-native.c. In other words, at this stage we assume that the platform has a XICS interrupt controller and we are using icp-native.c to drive it. Since the woken thread will need to acknowledge and clear the IPI, we also export the base physical address of the XICS registers using kvmppc_set_xics_phys() for use in the low-level KVM book3s code. When a vcpu is created, it is assigned to a virtual CPU core. The vcore number is obtained by dividing the vcpu number by the number of threads per core in the host. This number is exported to userspace via the KVM_CAP_PPC_SMT capability. If qemu wishes to run the guest in single-threaded mode, it should make all vcpu numbers be multiples of the number of threads per core. We distinguish three states of a vcpu: runnable (i.e., ready to execute the guest), blocked (that is, idle), and busy in host. We currently implement a policy that the vcore can run only when all its threads are runnable or blocked. This way, if a vcpu needs to execute elsewhere in the kernel or in qemu, it can do so without being starved of CPU by the other vcpus. When a vcore starts to run, it executes in the context of one of the vcpu threads. The other vcpu threads all go to sleep and stay asleep until something happens requiring the vcpu thread to return to qemu, or to wake up to run the vcore (this can happen when another vcpu thread goes from busy in host state to blocked). It can happen that a vcpu goes from blocked to runnable state (e.g. because of an interrupt), and the vcore it belongs to is already running. In that case it can start to run immediately as long as the none of the vcpus in the vcore have started to exit the guest. We send the next free thread in the vcore an IPI to get it to start to execute the guest. It synchronizes with the other threads via the vcore->entry_exit_count field to make sure that it doesn't go into the guest if the other vcpus are exiting by the time that it is ready to actually enter the guest. Note that there is no fixed relationship between the hardware thread number and the vcpu number. Hardware threads are assigned to vcpus as they become runnable, so we will always use the lower-numbered hardware threads in preference to higher-numbered threads if not all the vcpus in the vcore are runnable, regardless of which vcpus are runnable. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2011-06-29 08:23:08 +08:00
rlwinm. r13,r13,47-31,30,31
beq 9f
/* waking up from powersave (nap) state */
cmpwi cr1,r13,2
/* Total loss of HV state is fatal, we could try to use the
* PIR to locate a PACA, then use an emergency stack etc...
* OPAL v3 based powernv platforms have new idle states
* which fall in this catagory.
*/
bgt cr1,8f
KVM: PPC: Allow book3s_hv guests to use SMT processor modes This lifts the restriction that book3s_hv guests can only run one hardware thread per core, and allows them to use up to 4 threads per core on POWER7. The host still has to run single-threaded. This capability is advertised to qemu through a new KVM_CAP_PPC_SMT capability. The return value of the ioctl querying this capability is the number of vcpus per virtual CPU core (vcore), currently 4. To use this, the host kernel should be booted with all threads active, and then all the secondary threads should be offlined. This will put the secondary threads into nap mode. KVM will then wake them from nap mode and use them for running guest code (while they are still offline). To wake the secondary threads, we send them an IPI using a new xics_wake_cpu() function, implemented in arch/powerpc/sysdev/xics/icp-native.c. In other words, at this stage we assume that the platform has a XICS interrupt controller and we are using icp-native.c to drive it. Since the woken thread will need to acknowledge and clear the IPI, we also export the base physical address of the XICS registers using kvmppc_set_xics_phys() for use in the low-level KVM book3s code. When a vcpu is created, it is assigned to a virtual CPU core. The vcore number is obtained by dividing the vcpu number by the number of threads per core in the host. This number is exported to userspace via the KVM_CAP_PPC_SMT capability. If qemu wishes to run the guest in single-threaded mode, it should make all vcpu numbers be multiples of the number of threads per core. We distinguish three states of a vcpu: runnable (i.e., ready to execute the guest), blocked (that is, idle), and busy in host. We currently implement a policy that the vcore can run only when all its threads are runnable or blocked. This way, if a vcpu needs to execute elsewhere in the kernel or in qemu, it can do so without being starved of CPU by the other vcpus. When a vcore starts to run, it executes in the context of one of the vcpu threads. The other vcpu threads all go to sleep and stay asleep until something happens requiring the vcpu thread to return to qemu, or to wake up to run the vcore (this can happen when another vcpu thread goes from busy in host state to blocked). It can happen that a vcpu goes from blocked to runnable state (e.g. because of an interrupt), and the vcore it belongs to is already running. In that case it can start to run immediately as long as the none of the vcpus in the vcore have started to exit the guest. We send the next free thread in the vcore an IPI to get it to start to execute the guest. It synchronizes with the other threads via the vcore->entry_exit_count field to make sure that it doesn't go into the guest if the other vcpus are exiting by the time that it is ready to actually enter the guest. Note that there is no fixed relationship between the hardware thread number and the vcpu number. Hardware threads are assigned to vcpus as they become runnable, so we will always use the lower-numbered hardware threads in preference to higher-numbered threads if not all the vcpus in the vcore are runnable, regardless of which vcpus are runnable. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2011-06-29 08:23:08 +08:00
GET_PACA(r13)
#ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
li r0,KVM_HWTHREAD_IN_KERNEL
stb r0,HSTATE_HWTHREAD_STATE(r13)
/* Order setting hwthread_state vs. testing hwthread_req */
sync
lbz r0,HSTATE_HWTHREAD_REQ(r13)
cmpwi r0,0
beq 1f
KVM: PPC: Allow book3s_hv guests to use SMT processor modes This lifts the restriction that book3s_hv guests can only run one hardware thread per core, and allows them to use up to 4 threads per core on POWER7. The host still has to run single-threaded. This capability is advertised to qemu through a new KVM_CAP_PPC_SMT capability. The return value of the ioctl querying this capability is the number of vcpus per virtual CPU core (vcore), currently 4. To use this, the host kernel should be booted with all threads active, and then all the secondary threads should be offlined. This will put the secondary threads into nap mode. KVM will then wake them from nap mode and use them for running guest code (while they are still offline). To wake the secondary threads, we send them an IPI using a new xics_wake_cpu() function, implemented in arch/powerpc/sysdev/xics/icp-native.c. In other words, at this stage we assume that the platform has a XICS interrupt controller and we are using icp-native.c to drive it. Since the woken thread will need to acknowledge and clear the IPI, we also export the base physical address of the XICS registers using kvmppc_set_xics_phys() for use in the low-level KVM book3s code. When a vcpu is created, it is assigned to a virtual CPU core. The vcore number is obtained by dividing the vcpu number by the number of threads per core in the host. This number is exported to userspace via the KVM_CAP_PPC_SMT capability. If qemu wishes to run the guest in single-threaded mode, it should make all vcpu numbers be multiples of the number of threads per core. We distinguish three states of a vcpu: runnable (i.e., ready to execute the guest), blocked (that is, idle), and busy in host. We currently implement a policy that the vcore can run only when all its threads are runnable or blocked. This way, if a vcpu needs to execute elsewhere in the kernel or in qemu, it can do so without being starved of CPU by the other vcpus. When a vcore starts to run, it executes in the context of one of the vcpu threads. The other vcpu threads all go to sleep and stay asleep until something happens requiring the vcpu thread to return to qemu, or to wake up to run the vcore (this can happen when another vcpu thread goes from busy in host state to blocked). It can happen that a vcpu goes from blocked to runnable state (e.g. because of an interrupt), and the vcore it belongs to is already running. In that case it can start to run immediately as long as the none of the vcpus in the vcore have started to exit the guest. We send the next free thread in the vcore an IPI to get it to start to execute the guest. It synchronizes with the other threads via the vcore->entry_exit_count field to make sure that it doesn't go into the guest if the other vcpus are exiting by the time that it is ready to actually enter the guest. Note that there is no fixed relationship between the hardware thread number and the vcpu number. Hardware threads are assigned to vcpus as they become runnable, so we will always use the lower-numbered hardware threads in preference to higher-numbered threads if not all the vcpus in the vcore are runnable, regardless of which vcpus are runnable. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2011-06-29 08:23:08 +08:00
b kvm_start_guest
1:
#endif
beq cr1,2f
b power7_wakeup_noloss
2: b power7_wakeup_loss
/* Fast Sleep wakeup on PowerNV */
8: GET_PACA(r13)
b power7_wakeup_tb_loss
KVM: PPC: Allow book3s_hv guests to use SMT processor modes This lifts the restriction that book3s_hv guests can only run one hardware thread per core, and allows them to use up to 4 threads per core on POWER7. The host still has to run single-threaded. This capability is advertised to qemu through a new KVM_CAP_PPC_SMT capability. The return value of the ioctl querying this capability is the number of vcpus per virtual CPU core (vcore), currently 4. To use this, the host kernel should be booted with all threads active, and then all the secondary threads should be offlined. This will put the secondary threads into nap mode. KVM will then wake them from nap mode and use them for running guest code (while they are still offline). To wake the secondary threads, we send them an IPI using a new xics_wake_cpu() function, implemented in arch/powerpc/sysdev/xics/icp-native.c. In other words, at this stage we assume that the platform has a XICS interrupt controller and we are using icp-native.c to drive it. Since the woken thread will need to acknowledge and clear the IPI, we also export the base physical address of the XICS registers using kvmppc_set_xics_phys() for use in the low-level KVM book3s code. When a vcpu is created, it is assigned to a virtual CPU core. The vcore number is obtained by dividing the vcpu number by the number of threads per core in the host. This number is exported to userspace via the KVM_CAP_PPC_SMT capability. If qemu wishes to run the guest in single-threaded mode, it should make all vcpu numbers be multiples of the number of threads per core. We distinguish three states of a vcpu: runnable (i.e., ready to execute the guest), blocked (that is, idle), and busy in host. We currently implement a policy that the vcore can run only when all its threads are runnable or blocked. This way, if a vcpu needs to execute elsewhere in the kernel or in qemu, it can do so without being starved of CPU by the other vcpus. When a vcore starts to run, it executes in the context of one of the vcpu threads. The other vcpu threads all go to sleep and stay asleep until something happens requiring the vcpu thread to return to qemu, or to wake up to run the vcore (this can happen when another vcpu thread goes from busy in host state to blocked). It can happen that a vcpu goes from blocked to runnable state (e.g. because of an interrupt), and the vcore it belongs to is already running. In that case it can start to run immediately as long as the none of the vcpus in the vcore have started to exit the guest. We send the next free thread in the vcore an IPI to get it to start to execute the guest. It synchronizes with the other threads via the vcore->entry_exit_count field to make sure that it doesn't go into the guest if the other vcpus are exiting by the time that it is ready to actually enter the guest. Note that there is no fixed relationship between the hardware thread number and the vcpu number. Hardware threads are assigned to vcpus as they become runnable, so we will always use the lower-numbered hardware threads in preference to higher-numbered threads if not all the vcpus in the vcore are runnable, regardless of which vcpus are runnable. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2011-06-29 08:23:08 +08:00
9:
END_FTR_SECTION_IFSET(CPU_FTR_HVMODE | CPU_FTR_ARCH_206)
#endif /* CONFIG_PPC_P7_NAP */
EXCEPTION_PROLOG_PSERIES(PACA_EXGEN, system_reset_common, EXC_STD,
NOTEST, 0x100)
. = 0x200
machine_check_pSeries_1:
/* This is moved out of line as it can be patched by FW, but
* some code path might still want to branch into the original
* vector
*/
powerpc: Save CFAR before branching in interrupt entry paths Some of the interrupt vectors on 64-bit POWER server processors are only 32 bytes long, which is not enough for the full first-level interrupt handler. For these we currently just have a branch to an out-of-line handler. However, this means that we corrupt the CFAR (come-from address register) on POWER7 and later processors. To fix this, we split the EXCEPTION_PROLOG_1 macro into two pieces: EXCEPTION_PROLOG_0 contains the part up to the point where the CFAR is saved in the PACA, and EXCEPTION_PROLOG_1 contains the rest. We then put EXCEPTION_PROLOG_0 in the short interrupt vectors before we branch to the out-of-line handler, which contains the rest of the first-level interrupt handler. To facilitate this, we define new _OOL (out of line) variants of STD_EXCEPTION_PSERIES, etc. In order to get EXCEPTION_PROLOG_0 to be short enough, i.e., no more than 6 instructions, it was necessary to move the stores that move the PPR and CFAR values into the PACA into __EXCEPTION_PROLOG_1 and to get rid of one of the two HMT_MEDIUM instructions. Previously there was a HMT_MEDIUM_PPR_DISCARD before the prolog, which was nop'd out on processors with the PPR (POWER7 and later), and then another HMT_MEDIUM inside the HMT_MEDIUM_PPR_SAVE macro call inside __EXCEPTION_PROLOG_1, which was nop'd out on processors without PPR. Now the HMT_MEDIUM inside EXCEPTION_PROLOG_0 is there unconditionally and the HMT_MEDIUM_PPR_DISCARD is not strictly necessary, although this leaves it in for the interrupt vectors where there is room for it. Previously we had a handler for hypervisor maintenance interrupts at 0xe50, which doesn't leave enough room for the vector for hypervisor emulation assist interrupts at 0xe40, since we need 8 instructions. The 0xe50 vector was only used on POWER6, as the HMI vector was moved to 0xe60 on POWER7. Since we don't support running in hypervisor mode on POWER6, we just remove the handler at 0xe50. This also changes denorm_exception_hv to use EXCEPTION_PROLOG_0 instead of open-coding it, and removes the HMT_MEDIUM_PPR_DISCARD from the relocation-on vectors (since any CPU that supports relocation-on interrupts also has the PPR). Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-02-05 02:10:15 +08:00
HMT_MEDIUM_PPR_DISCARD
SET_SCRATCH0(r13) /* save r13 */
#ifdef CONFIG_PPC_P7_NAP
BEGIN_FTR_SECTION
/* Running native on arch 2.06 or later, check if we are
* waking up from nap. We only handle no state loss and
* supervisor state loss. We do -not- handle hypervisor
* state loss at this time.
*/
mfspr r13,SPRN_SRR1
rlwinm. r13,r13,47-31,30,31
OPT_GET_SPR(r13, SPRN_CFAR, CPU_FTR_CFAR)
beq 9f
mfspr r13,SPRN_SRR1
rlwinm. r13,r13,47-31,30,31
/* waking up from powersave (nap) state */
cmpwi cr1,r13,2
/* Total loss of HV state is fatal. let's just stay stuck here */
OPT_GET_SPR(r13, SPRN_CFAR, CPU_FTR_CFAR)
bgt cr1,.
9:
OPT_SET_SPR(r13, SPRN_CFAR, CPU_FTR_CFAR)
END_FTR_SECTION_IFSET(CPU_FTR_HVMODE | CPU_FTR_ARCH_206)
#endif /* CONFIG_PPC_P7_NAP */
powerpc: Save CFAR before branching in interrupt entry paths Some of the interrupt vectors on 64-bit POWER server processors are only 32 bytes long, which is not enough for the full first-level interrupt handler. For these we currently just have a branch to an out-of-line handler. However, this means that we corrupt the CFAR (come-from address register) on POWER7 and later processors. To fix this, we split the EXCEPTION_PROLOG_1 macro into two pieces: EXCEPTION_PROLOG_0 contains the part up to the point where the CFAR is saved in the PACA, and EXCEPTION_PROLOG_1 contains the rest. We then put EXCEPTION_PROLOG_0 in the short interrupt vectors before we branch to the out-of-line handler, which contains the rest of the first-level interrupt handler. To facilitate this, we define new _OOL (out of line) variants of STD_EXCEPTION_PSERIES, etc. In order to get EXCEPTION_PROLOG_0 to be short enough, i.e., no more than 6 instructions, it was necessary to move the stores that move the PPR and CFAR values into the PACA into __EXCEPTION_PROLOG_1 and to get rid of one of the two HMT_MEDIUM instructions. Previously there was a HMT_MEDIUM_PPR_DISCARD before the prolog, which was nop'd out on processors with the PPR (POWER7 and later), and then another HMT_MEDIUM inside the HMT_MEDIUM_PPR_SAVE macro call inside __EXCEPTION_PROLOG_1, which was nop'd out on processors without PPR. Now the HMT_MEDIUM inside EXCEPTION_PROLOG_0 is there unconditionally and the HMT_MEDIUM_PPR_DISCARD is not strictly necessary, although this leaves it in for the interrupt vectors where there is room for it. Previously we had a handler for hypervisor maintenance interrupts at 0xe50, which doesn't leave enough room for the vector for hypervisor emulation assist interrupts at 0xe40, since we need 8 instructions. The 0xe50 vector was only used on POWER6, as the HMI vector was moved to 0xe60 on POWER7. Since we don't support running in hypervisor mode on POWER6, we just remove the handler at 0xe50. This also changes denorm_exception_hv to use EXCEPTION_PROLOG_0 instead of open-coding it, and removes the HMT_MEDIUM_PPR_DISCARD from the relocation-on vectors (since any CPU that supports relocation-on interrupts also has the PPR). Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-02-05 02:10:15 +08:00
EXCEPTION_PROLOG_0(PACA_EXMC)
powerpc/book3s: handle machine check in Linux host. Move machine check entry point into Linux. So far we were dependent on firmware to decode MCE error details and handover the high level info to OS. This patch introduces early machine check routine that saves the MCE information (srr1, srr0, dar and dsisr) to the emergency stack. We allocate stack frame on emergency stack and set the r1 accordingly. This allows us to be prepared to take another exception without loosing context. One thing to note here that, if we get another machine check while ME bit is off then we risk a checkstop. Hence we restrict ourselves to save only MCE information and register saved on PACA_EXMC save are before we turn the ME bit on. We use paca->in_mce flag to differentiate between first entry and nested machine check entry which helps proper use of emergency stack. We increment paca->in_mce every time we enter in early machine check handler and decrement it while leaving. When we enter machine check early handler first time (paca->in_mce == 0), we are sure nobody is using MC emergency stack and allocate a stack frame at the start of the emergency stack. During subsequent entry (paca->in_mce > 0), we know that r1 points inside emergency stack and we allocate separate stack frame accordingly. This prevents us from clobbering MCE information during nested machine checks. The early machine check handler changes are placed under CPU_FTR_HVMODE section. This makes sure that the early machine check handler will get executed only in hypervisor kernel. This is the code flow: Machine Check Interrupt | V 0x200 vector ME=0, IR=0, DR=0 | V +-----------------------------------------------+ |machine_check_pSeries_early: | ME=0, IR=0, DR=0 | Alloc frame on emergency stack | | Save srr1, srr0, dar and dsisr on stack | +-----------------------------------------------+ | (ME=1, IR=0, DR=0, RFID) | V machine_check_handle_early ME=1, IR=0, DR=0 | V +-----------------------------------------------+ | machine_check_early (r3=pt_regs) | ME=1, IR=0, DR=0 | Things to do: (in next patches) | | Flush SLB for SLB errors | | Flush TLB for TLB errors | | Decode and save MCE info | +-----------------------------------------------+ | (Fall through existing exception handler routine.) | V machine_check_pSerie ME=1, IR=0, DR=0 | (ME=1, IR=1, DR=1, RFID) | V machine_check_common ME=1, IR=1, DR=1 . . . Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-10-30 22:34:08 +08:00
BEGIN_FTR_SECTION
b machine_check_pSeries_early
FTR_SECTION_ELSE
powerpc: Save CFAR before branching in interrupt entry paths Some of the interrupt vectors on 64-bit POWER server processors are only 32 bytes long, which is not enough for the full first-level interrupt handler. For these we currently just have a branch to an out-of-line handler. However, this means that we corrupt the CFAR (come-from address register) on POWER7 and later processors. To fix this, we split the EXCEPTION_PROLOG_1 macro into two pieces: EXCEPTION_PROLOG_0 contains the part up to the point where the CFAR is saved in the PACA, and EXCEPTION_PROLOG_1 contains the rest. We then put EXCEPTION_PROLOG_0 in the short interrupt vectors before we branch to the out-of-line handler, which contains the rest of the first-level interrupt handler. To facilitate this, we define new _OOL (out of line) variants of STD_EXCEPTION_PSERIES, etc. In order to get EXCEPTION_PROLOG_0 to be short enough, i.e., no more than 6 instructions, it was necessary to move the stores that move the PPR and CFAR values into the PACA into __EXCEPTION_PROLOG_1 and to get rid of one of the two HMT_MEDIUM instructions. Previously there was a HMT_MEDIUM_PPR_DISCARD before the prolog, which was nop'd out on processors with the PPR (POWER7 and later), and then another HMT_MEDIUM inside the HMT_MEDIUM_PPR_SAVE macro call inside __EXCEPTION_PROLOG_1, which was nop'd out on processors without PPR. Now the HMT_MEDIUM inside EXCEPTION_PROLOG_0 is there unconditionally and the HMT_MEDIUM_PPR_DISCARD is not strictly necessary, although this leaves it in for the interrupt vectors where there is room for it. Previously we had a handler for hypervisor maintenance interrupts at 0xe50, which doesn't leave enough room for the vector for hypervisor emulation assist interrupts at 0xe40, since we need 8 instructions. The 0xe50 vector was only used on POWER6, as the HMI vector was moved to 0xe60 on POWER7. Since we don't support running in hypervisor mode on POWER6, we just remove the handler at 0xe50. This also changes denorm_exception_hv to use EXCEPTION_PROLOG_0 instead of open-coding it, and removes the HMT_MEDIUM_PPR_DISCARD from the relocation-on vectors (since any CPU that supports relocation-on interrupts also has the PPR). Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-02-05 02:10:15 +08:00
b machine_check_pSeries_0
powerpc/book3s: handle machine check in Linux host. Move machine check entry point into Linux. So far we were dependent on firmware to decode MCE error details and handover the high level info to OS. This patch introduces early machine check routine that saves the MCE information (srr1, srr0, dar and dsisr) to the emergency stack. We allocate stack frame on emergency stack and set the r1 accordingly. This allows us to be prepared to take another exception without loosing context. One thing to note here that, if we get another machine check while ME bit is off then we risk a checkstop. Hence we restrict ourselves to save only MCE information and register saved on PACA_EXMC save are before we turn the ME bit on. We use paca->in_mce flag to differentiate between first entry and nested machine check entry which helps proper use of emergency stack. We increment paca->in_mce every time we enter in early machine check handler and decrement it while leaving. When we enter machine check early handler first time (paca->in_mce == 0), we are sure nobody is using MC emergency stack and allocate a stack frame at the start of the emergency stack. During subsequent entry (paca->in_mce > 0), we know that r1 points inside emergency stack and we allocate separate stack frame accordingly. This prevents us from clobbering MCE information during nested machine checks. The early machine check handler changes are placed under CPU_FTR_HVMODE section. This makes sure that the early machine check handler will get executed only in hypervisor kernel. This is the code flow: Machine Check Interrupt | V 0x200 vector ME=0, IR=0, DR=0 | V +-----------------------------------------------+ |machine_check_pSeries_early: | ME=0, IR=0, DR=0 | Alloc frame on emergency stack | | Save srr1, srr0, dar and dsisr on stack | +-----------------------------------------------+ | (ME=1, IR=0, DR=0, RFID) | V machine_check_handle_early ME=1, IR=0, DR=0 | V +-----------------------------------------------+ | machine_check_early (r3=pt_regs) | ME=1, IR=0, DR=0 | Things to do: (in next patches) | | Flush SLB for SLB errors | | Flush TLB for TLB errors | | Decode and save MCE info | +-----------------------------------------------+ | (Fall through existing exception handler routine.) | V machine_check_pSerie ME=1, IR=0, DR=0 | (ME=1, IR=1, DR=1, RFID) | V machine_check_common ME=1, IR=1, DR=1 . . . Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-10-30 22:34:08 +08:00
ALT_FTR_SECTION_END_IFSET(CPU_FTR_HVMODE)
. = 0x300
.globl data_access_pSeries
data_access_pSeries:
HMT_MEDIUM_PPR_DISCARD
SET_SCRATCH0(r13)
EXCEPTION_PROLOG_PSERIES(PACA_EXGEN, data_access_common, EXC_STD,
KVMTEST, 0x300)
. = 0x380
.globl data_access_slb_pSeries
data_access_slb_pSeries:
HMT_MEDIUM_PPR_DISCARD
SET_SCRATCH0(r13)
powerpc: Save CFAR before branching in interrupt entry paths Some of the interrupt vectors on 64-bit POWER server processors are only 32 bytes long, which is not enough for the full first-level interrupt handler. For these we currently just have a branch to an out-of-line handler. However, this means that we corrupt the CFAR (come-from address register) on POWER7 and later processors. To fix this, we split the EXCEPTION_PROLOG_1 macro into two pieces: EXCEPTION_PROLOG_0 contains the part up to the point where the CFAR is saved in the PACA, and EXCEPTION_PROLOG_1 contains the rest. We then put EXCEPTION_PROLOG_0 in the short interrupt vectors before we branch to the out-of-line handler, which contains the rest of the first-level interrupt handler. To facilitate this, we define new _OOL (out of line) variants of STD_EXCEPTION_PSERIES, etc. In order to get EXCEPTION_PROLOG_0 to be short enough, i.e., no more than 6 instructions, it was necessary to move the stores that move the PPR and CFAR values into the PACA into __EXCEPTION_PROLOG_1 and to get rid of one of the two HMT_MEDIUM instructions. Previously there was a HMT_MEDIUM_PPR_DISCARD before the prolog, which was nop'd out on processors with the PPR (POWER7 and later), and then another HMT_MEDIUM inside the HMT_MEDIUM_PPR_SAVE macro call inside __EXCEPTION_PROLOG_1, which was nop'd out on processors without PPR. Now the HMT_MEDIUM inside EXCEPTION_PROLOG_0 is there unconditionally and the HMT_MEDIUM_PPR_DISCARD is not strictly necessary, although this leaves it in for the interrupt vectors where there is room for it. Previously we had a handler for hypervisor maintenance interrupts at 0xe50, which doesn't leave enough room for the vector for hypervisor emulation assist interrupts at 0xe40, since we need 8 instructions. The 0xe50 vector was only used on POWER6, as the HMI vector was moved to 0xe60 on POWER7. Since we don't support running in hypervisor mode on POWER6, we just remove the handler at 0xe50. This also changes denorm_exception_hv to use EXCEPTION_PROLOG_0 instead of open-coding it, and removes the HMT_MEDIUM_PPR_DISCARD from the relocation-on vectors (since any CPU that supports relocation-on interrupts also has the PPR). Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-02-05 02:10:15 +08:00
EXCEPTION_PROLOG_0(PACA_EXSLB)
EXCEPTION_PROLOG_1(PACA_EXSLB, KVMTEST, 0x380)
std r3,PACA_EXSLB+EX_R3(r13)
mfspr r3,SPRN_DAR
#ifdef __DISABLED__
/* Keep that around for when we re-implement dynamic VSIDs */
cmpdi r3,0
bge slb_miss_user_pseries
#endif /* __DISABLED__ */
mfspr r12,SPRN_SRR1
#ifndef CONFIG_RELOCATABLE
b slb_miss_realmode
#else
/*
* We can't just use a direct branch to slb_miss_realmode
* because the distance from here to there depends on where
* the kernel ends up being put.
*/
mfctr r11
ld r10,PACAKBASE(r13)
LOAD_HANDLER(r10, slb_miss_realmode)
mtctr r10
bctr
#endif
STD_EXCEPTION_PSERIES(0x400, 0x400, instruction_access)
. = 0x480
.globl instruction_access_slb_pSeries
instruction_access_slb_pSeries:
HMT_MEDIUM_PPR_DISCARD
SET_SCRATCH0(r13)
powerpc: Save CFAR before branching in interrupt entry paths Some of the interrupt vectors on 64-bit POWER server processors are only 32 bytes long, which is not enough for the full first-level interrupt handler. For these we currently just have a branch to an out-of-line handler. However, this means that we corrupt the CFAR (come-from address register) on POWER7 and later processors. To fix this, we split the EXCEPTION_PROLOG_1 macro into two pieces: EXCEPTION_PROLOG_0 contains the part up to the point where the CFAR is saved in the PACA, and EXCEPTION_PROLOG_1 contains the rest. We then put EXCEPTION_PROLOG_0 in the short interrupt vectors before we branch to the out-of-line handler, which contains the rest of the first-level interrupt handler. To facilitate this, we define new _OOL (out of line) variants of STD_EXCEPTION_PSERIES, etc. In order to get EXCEPTION_PROLOG_0 to be short enough, i.e., no more than 6 instructions, it was necessary to move the stores that move the PPR and CFAR values into the PACA into __EXCEPTION_PROLOG_1 and to get rid of one of the two HMT_MEDIUM instructions. Previously there was a HMT_MEDIUM_PPR_DISCARD before the prolog, which was nop'd out on processors with the PPR (POWER7 and later), and then another HMT_MEDIUM inside the HMT_MEDIUM_PPR_SAVE macro call inside __EXCEPTION_PROLOG_1, which was nop'd out on processors without PPR. Now the HMT_MEDIUM inside EXCEPTION_PROLOG_0 is there unconditionally and the HMT_MEDIUM_PPR_DISCARD is not strictly necessary, although this leaves it in for the interrupt vectors where there is room for it. Previously we had a handler for hypervisor maintenance interrupts at 0xe50, which doesn't leave enough room for the vector for hypervisor emulation assist interrupts at 0xe40, since we need 8 instructions. The 0xe50 vector was only used on POWER6, as the HMI vector was moved to 0xe60 on POWER7. Since we don't support running in hypervisor mode on POWER6, we just remove the handler at 0xe50. This also changes denorm_exception_hv to use EXCEPTION_PROLOG_0 instead of open-coding it, and removes the HMT_MEDIUM_PPR_DISCARD from the relocation-on vectors (since any CPU that supports relocation-on interrupts also has the PPR). Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-02-05 02:10:15 +08:00
EXCEPTION_PROLOG_0(PACA_EXSLB)
KVM: PPC: Add support for Book3S processors in hypervisor mode This adds support for KVM running on 64-bit Book 3S processors, specifically POWER7, in hypervisor mode. Using hypervisor mode means that the guest can use the processor's supervisor mode. That means that the guest can execute privileged instructions and access privileged registers itself without trapping to the host. This gives excellent performance, but does mean that KVM cannot emulate a processor architecture other than the one that the hardware implements. This code assumes that the guest is running paravirtualized using the PAPR (Power Architecture Platform Requirements) interface, which is the interface that IBM's PowerVM hypervisor uses. That means that existing Linux distributions that run on IBM pSeries machines will also run under KVM without modification. In order to communicate the PAPR hypercalls to qemu, this adds a new KVM_EXIT_PAPR_HCALL exit code to include/linux/kvm.h. Currently the choice between book3s_hv support and book3s_pr support (i.e. the existing code, which runs the guest in user mode) has to be made at kernel configuration time, so a given kernel binary can only do one or the other. This new book3s_hv code doesn't support MMIO emulation at present. Since we are running paravirtualized guests, this isn't a serious restriction. With the guest running in supervisor mode, most exceptions go straight to the guest. We will never get data or instruction storage or segment interrupts, alignment interrupts, decrementer interrupts, program interrupts, single-step interrupts, etc., coming to the hypervisor from the guest. Therefore this introduces a new KVMTEST_NONHV macro for the exception entry path so that we don't have to do the KVM test on entry to those exception handlers. We do however get hypervisor decrementer, hypervisor data storage, hypervisor instruction storage, and hypervisor emulation assist interrupts, so we have to handle those. In hypervisor mode, real-mode accesses can access all of RAM, not just a limited amount. Therefore we put all the guest state in the vcpu.arch and use the shadow_vcpu in the PACA only for temporary scratch space. We allocate the vcpu with kzalloc rather than vzalloc, and we don't use anything in the kvmppc_vcpu_book3s struct, so we don't allocate it. We don't have a shared page with the guest, but we still need a kvm_vcpu_arch_shared struct to store the values of various registers, so we include one in the vcpu_arch struct. The POWER7 processor has a restriction that all threads in a core have to be in the same partition. MMU-on kernel code counts as a partition (partition 0), so we have to do a partition switch on every entry to and exit from the guest. At present we require the host and guest to run in single-thread mode because of this hardware restriction. This code allocates a hashed page table for the guest and initializes it with HPTEs for the guest's Virtual Real Memory Area (VRMA). We require that the guest memory is allocated using 16MB huge pages, in order to simplify the low-level memory management. This also means that we can get away without tracking paging activity in the host for now, since huge pages can't be paged or swapped. This also adds a few new exports needed by the book3s_hv code. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2011-06-29 08:21:34 +08:00
EXCEPTION_PROLOG_1(PACA_EXSLB, KVMTEST_PR, 0x480)
std r3,PACA_EXSLB+EX_R3(r13)
mfspr r3,SPRN_SRR0 /* SRR0 is faulting address */
#ifdef __DISABLED__
/* Keep that around for when we re-implement dynamic VSIDs */
cmpdi r3,0
bge slb_miss_user_pseries
#endif /* __DISABLED__ */
mfspr r12,SPRN_SRR1
#ifndef CONFIG_RELOCATABLE
b slb_miss_realmode
#else
mfctr r11
ld r10,PACAKBASE(r13)
LOAD_HANDLER(r10, slb_miss_realmode)
mtctr r10
bctr
#endif
/* We open code these as we can't have a ". = x" (even with
* x = "." within a feature section
*/
. = 0x500;
.globl hardware_interrupt_pSeries;
.globl hardware_interrupt_hv;
hardware_interrupt_pSeries:
hardware_interrupt_hv:
powerpc: Fix "attempt to move .org backwards" error Building a 64-bit powerpc kernel with PR KVM enabled currently gives this error: AS arch/powerpc/kernel/head_64.o arch/powerpc/kernel/exceptions-64s.S: Assembler messages: arch/powerpc/kernel/exceptions-64s.S:258: Error: attempt to move .org backwards make[2]: *** [arch/powerpc/kernel/head_64.o] Error 1 This happens because the MASKABLE_EXCEPTION_PSERIES macro turns into 33 instructions, but we only have space for 32 at the decrementer interrupt vector (from 0x900 to 0x980). In the code generated by the MASKABLE_EXCEPTION_PSERIES macro, we currently have two instances of the HMT_MEDIUM macro, which has the effect of setting the SMT thread priority to medium. One is the first instruction, and is overwritten by a no-op on processors where we save the PPR (processor priority register), that is, POWER7 or later. The other is after we have saved the PPR. In order to reduce the code at 0x900 by one instruction, we omit the first HMT_MEDIUM. On processors without SMT this will have no effect since HMT_MEDIUM is a no-op there. On POWER5 and RS64 machines this will mean that the first few instructions take a little longer in the case where a decrementer interrupt occurs when the hardware thread is running at low SMT priority. On POWER6 and later machines, the hardware automatically boosts the thread priority when a decrementer interrupt is taken if the thread priority was below medium, so this change won't make any difference. The alternative would be to branch out of line after saving the CFAR. However, that would incur an extra overhead on all processors, whereas the approach adopted here only adds overhead on older threaded processors. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-04-26 01:51:40 +08:00
HMT_MEDIUM_PPR_DISCARD
BEGIN_FTR_SECTION
_MASKABLE_EXCEPTION_PSERIES(0x502, hardware_interrupt,
EXC_HV, SOFTEN_TEST_HV)
KVM_HANDLER(PACA_EXGEN, EXC_HV, 0x502)
KVM: PPC: Add support for Book3S processors in hypervisor mode This adds support for KVM running on 64-bit Book 3S processors, specifically POWER7, in hypervisor mode. Using hypervisor mode means that the guest can use the processor's supervisor mode. That means that the guest can execute privileged instructions and access privileged registers itself without trapping to the host. This gives excellent performance, but does mean that KVM cannot emulate a processor architecture other than the one that the hardware implements. This code assumes that the guest is running paravirtualized using the PAPR (Power Architecture Platform Requirements) interface, which is the interface that IBM's PowerVM hypervisor uses. That means that existing Linux distributions that run on IBM pSeries machines will also run under KVM without modification. In order to communicate the PAPR hypercalls to qemu, this adds a new KVM_EXIT_PAPR_HCALL exit code to include/linux/kvm.h. Currently the choice between book3s_hv support and book3s_pr support (i.e. the existing code, which runs the guest in user mode) has to be made at kernel configuration time, so a given kernel binary can only do one or the other. This new book3s_hv code doesn't support MMIO emulation at present. Since we are running paravirtualized guests, this isn't a serious restriction. With the guest running in supervisor mode, most exceptions go straight to the guest. We will never get data or instruction storage or segment interrupts, alignment interrupts, decrementer interrupts, program interrupts, single-step interrupts, etc., coming to the hypervisor from the guest. Therefore this introduces a new KVMTEST_NONHV macro for the exception entry path so that we don't have to do the KVM test on entry to those exception handlers. We do however get hypervisor decrementer, hypervisor data storage, hypervisor instruction storage, and hypervisor emulation assist interrupts, so we have to handle those. In hypervisor mode, real-mode accesses can access all of RAM, not just a limited amount. Therefore we put all the guest state in the vcpu.arch and use the shadow_vcpu in the PACA only for temporary scratch space. We allocate the vcpu with kzalloc rather than vzalloc, and we don't use anything in the kvmppc_vcpu_book3s struct, so we don't allocate it. We don't have a shared page with the guest, but we still need a kvm_vcpu_arch_shared struct to store the values of various registers, so we include one in the vcpu_arch struct. The POWER7 processor has a restriction that all threads in a core have to be in the same partition. MMU-on kernel code counts as a partition (partition 0), so we have to do a partition switch on every entry to and exit from the guest. At present we require the host and guest to run in single-thread mode because of this hardware restriction. This code allocates a hashed page table for the guest and initializes it with HPTEs for the guest's Virtual Real Memory Area (VRMA). We require that the guest memory is allocated using 16MB huge pages, in order to simplify the low-level memory management. This also means that we can get away without tracking paging activity in the host for now, since huge pages can't be paged or swapped. This also adds a few new exports needed by the book3s_hv code. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2011-06-29 08:21:34 +08:00
FTR_SECTION_ELSE
_MASKABLE_EXCEPTION_PSERIES(0x500, hardware_interrupt,
KVM: PPC: book3s_hv: Add support for PPC970-family processors This adds support for running KVM guests in supervisor mode on those PPC970 processors that have a usable hypervisor mode. Unfortunately, Apple G5 machines have supervisor mode disabled (MSR[HV] is forced to 1), but the YDL PowerStation does have a usable hypervisor mode. There are several differences between the PPC970 and POWER7 in how guests are managed. These differences are accommodated using the CPU_FTR_ARCH_201 (PPC970) and CPU_FTR_ARCH_206 (POWER7) CPU feature bits. Notably, on PPC970: * The LPCR, LPID or RMOR registers don't exist, and the functions of those registers are provided by bits in HID4 and one bit in HID0. * External interrupts can be directed to the hypervisor, but unlike POWER7 they are masked by MSR[EE] in non-hypervisor modes and use SRR0/1 not HSRR0/1. * There is no virtual RMA (VRMA) mode; the guest must use an RMO (real mode offset) area. * The TLB entries are not tagged with the LPID, so it is necessary to flush the whole TLB on partition switch. Furthermore, when switching partitions we have to ensure that no other CPU is executing the tlbie or tlbsync instructions in either the old or the new partition, otherwise undefined behaviour can occur. * The PMU has 8 counters (PMC registers) rather than 6. * The DSCR, PURR, SPURR, AMR, AMOR, UAMOR registers don't exist. * The SLB has 64 entries rather than 32. * There is no mediated external interrupt facility, so if we switch to a guest that has a virtual external interrupt pending but the guest has MSR[EE] = 0, we have to arrange to have an interrupt pending for it so that we can get control back once it re-enables interrupts. We do that by sending ourselves an IPI with smp_send_reschedule after hard-disabling interrupts. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2011-06-29 08:40:08 +08:00
EXC_STD, SOFTEN_TEST_HV_201)
KVM: PPC: Add support for Book3S processors in hypervisor mode This adds support for KVM running on 64-bit Book 3S processors, specifically POWER7, in hypervisor mode. Using hypervisor mode means that the guest can use the processor's supervisor mode. That means that the guest can execute privileged instructions and access privileged registers itself without trapping to the host. This gives excellent performance, but does mean that KVM cannot emulate a processor architecture other than the one that the hardware implements. This code assumes that the guest is running paravirtualized using the PAPR (Power Architecture Platform Requirements) interface, which is the interface that IBM's PowerVM hypervisor uses. That means that existing Linux distributions that run on IBM pSeries machines will also run under KVM without modification. In order to communicate the PAPR hypercalls to qemu, this adds a new KVM_EXIT_PAPR_HCALL exit code to include/linux/kvm.h. Currently the choice between book3s_hv support and book3s_pr support (i.e. the existing code, which runs the guest in user mode) has to be made at kernel configuration time, so a given kernel binary can only do one or the other. This new book3s_hv code doesn't support MMIO emulation at present. Since we are running paravirtualized guests, this isn't a serious restriction. With the guest running in supervisor mode, most exceptions go straight to the guest. We will never get data or instruction storage or segment interrupts, alignment interrupts, decrementer interrupts, program interrupts, single-step interrupts, etc., coming to the hypervisor from the guest. Therefore this introduces a new KVMTEST_NONHV macro for the exception entry path so that we don't have to do the KVM test on entry to those exception handlers. We do however get hypervisor decrementer, hypervisor data storage, hypervisor instruction storage, and hypervisor emulation assist interrupts, so we have to handle those. In hypervisor mode, real-mode accesses can access all of RAM, not just a limited amount. Therefore we put all the guest state in the vcpu.arch and use the shadow_vcpu in the PACA only for temporary scratch space. We allocate the vcpu with kzalloc rather than vzalloc, and we don't use anything in the kvmppc_vcpu_book3s struct, so we don't allocate it. We don't have a shared page with the guest, but we still need a kvm_vcpu_arch_shared struct to store the values of various registers, so we include one in the vcpu_arch struct. The POWER7 processor has a restriction that all threads in a core have to be in the same partition. MMU-on kernel code counts as a partition (partition 0), so we have to do a partition switch on every entry to and exit from the guest. At present we require the host and guest to run in single-thread mode because of this hardware restriction. This code allocates a hashed page table for the guest and initializes it with HPTEs for the guest's Virtual Real Memory Area (VRMA). We require that the guest memory is allocated using 16MB huge pages, in order to simplify the low-level memory management. This also means that we can get away without tracking paging activity in the host for now, since huge pages can't be paged or swapped. This also adds a few new exports needed by the book3s_hv code. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2011-06-29 08:21:34 +08:00
KVM_HANDLER(PACA_EXGEN, EXC_STD, 0x500)
ALT_FTR_SECTION_END_IFSET(CPU_FTR_HVMODE | CPU_FTR_ARCH_206)
STD_EXCEPTION_PSERIES(0x600, 0x600, alignment)
KVM: PPC: Add support for Book3S processors in hypervisor mode This adds support for KVM running on 64-bit Book 3S processors, specifically POWER7, in hypervisor mode. Using hypervisor mode means that the guest can use the processor's supervisor mode. That means that the guest can execute privileged instructions and access privileged registers itself without trapping to the host. This gives excellent performance, but does mean that KVM cannot emulate a processor architecture other than the one that the hardware implements. This code assumes that the guest is running paravirtualized using the PAPR (Power Architecture Platform Requirements) interface, which is the interface that IBM's PowerVM hypervisor uses. That means that existing Linux distributions that run on IBM pSeries machines will also run under KVM without modification. In order to communicate the PAPR hypercalls to qemu, this adds a new KVM_EXIT_PAPR_HCALL exit code to include/linux/kvm.h. Currently the choice between book3s_hv support and book3s_pr support (i.e. the existing code, which runs the guest in user mode) has to be made at kernel configuration time, so a given kernel binary can only do one or the other. This new book3s_hv code doesn't support MMIO emulation at present. Since we are running paravirtualized guests, this isn't a serious restriction. With the guest running in supervisor mode, most exceptions go straight to the guest. We will never get data or instruction storage or segment interrupts, alignment interrupts, decrementer interrupts, program interrupts, single-step interrupts, etc., coming to the hypervisor from the guest. Therefore this introduces a new KVMTEST_NONHV macro for the exception entry path so that we don't have to do the KVM test on entry to those exception handlers. We do however get hypervisor decrementer, hypervisor data storage, hypervisor instruction storage, and hypervisor emulation assist interrupts, so we have to handle those. In hypervisor mode, real-mode accesses can access all of RAM, not just a limited amount. Therefore we put all the guest state in the vcpu.arch and use the shadow_vcpu in the PACA only for temporary scratch space. We allocate the vcpu with kzalloc rather than vzalloc, and we don't use anything in the kvmppc_vcpu_book3s struct, so we don't allocate it. We don't have a shared page with the guest, but we still need a kvm_vcpu_arch_shared struct to store the values of various registers, so we include one in the vcpu_arch struct. The POWER7 processor has a restriction that all threads in a core have to be in the same partition. MMU-on kernel code counts as a partition (partition 0), so we have to do a partition switch on every entry to and exit from the guest. At present we require the host and guest to run in single-thread mode because of this hardware restriction. This code allocates a hashed page table for the guest and initializes it with HPTEs for the guest's Virtual Real Memory Area (VRMA). We require that the guest memory is allocated using 16MB huge pages, in order to simplify the low-level memory management. This also means that we can get away without tracking paging activity in the host for now, since huge pages can't be paged or swapped. This also adds a few new exports needed by the book3s_hv code. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2011-06-29 08:21:34 +08:00
KVM_HANDLER_PR(PACA_EXGEN, EXC_STD, 0x600)
STD_EXCEPTION_PSERIES(0x700, 0x700, program_check)
KVM: PPC: Add support for Book3S processors in hypervisor mode This adds support for KVM running on 64-bit Book 3S processors, specifically POWER7, in hypervisor mode. Using hypervisor mode means that the guest can use the processor's supervisor mode. That means that the guest can execute privileged instructions and access privileged registers itself without trapping to the host. This gives excellent performance, but does mean that KVM cannot emulate a processor architecture other than the one that the hardware implements. This code assumes that the guest is running paravirtualized using the PAPR (Power Architecture Platform Requirements) interface, which is the interface that IBM's PowerVM hypervisor uses. That means that existing Linux distributions that run on IBM pSeries machines will also run under KVM without modification. In order to communicate the PAPR hypercalls to qemu, this adds a new KVM_EXIT_PAPR_HCALL exit code to include/linux/kvm.h. Currently the choice between book3s_hv support and book3s_pr support (i.e. the existing code, which runs the guest in user mode) has to be made at kernel configuration time, so a given kernel binary can only do one or the other. This new book3s_hv code doesn't support MMIO emulation at present. Since we are running paravirtualized guests, this isn't a serious restriction. With the guest running in supervisor mode, most exceptions go straight to the guest. We will never get data or instruction storage or segment interrupts, alignment interrupts, decrementer interrupts, program interrupts, single-step interrupts, etc., coming to the hypervisor from the guest. Therefore this introduces a new KVMTEST_NONHV macro for the exception entry path so that we don't have to do the KVM test on entry to those exception handlers. We do however get hypervisor decrementer, hypervisor data storage, hypervisor instruction storage, and hypervisor emulation assist interrupts, so we have to handle those. In hypervisor mode, real-mode accesses can access all of RAM, not just a limited amount. Therefore we put all the guest state in the vcpu.arch and use the shadow_vcpu in the PACA only for temporary scratch space. We allocate the vcpu with kzalloc rather than vzalloc, and we don't use anything in the kvmppc_vcpu_book3s struct, so we don't allocate it. We don't have a shared page with the guest, but we still need a kvm_vcpu_arch_shared struct to store the values of various registers, so we include one in the vcpu_arch struct. The POWER7 processor has a restriction that all threads in a core have to be in the same partition. MMU-on kernel code counts as a partition (partition 0), so we have to do a partition switch on every entry to and exit from the guest. At present we require the host and guest to run in single-thread mode because of this hardware restriction. This code allocates a hashed page table for the guest and initializes it with HPTEs for the guest's Virtual Real Memory Area (VRMA). We require that the guest memory is allocated using 16MB huge pages, in order to simplify the low-level memory management. This also means that we can get away without tracking paging activity in the host for now, since huge pages can't be paged or swapped. This also adds a few new exports needed by the book3s_hv code. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2011-06-29 08:21:34 +08:00
KVM_HANDLER_PR(PACA_EXGEN, EXC_STD, 0x700)
STD_EXCEPTION_PSERIES(0x800, 0x800, fp_unavailable)
KVM: PPC: Add support for Book3S processors in hypervisor mode This adds support for KVM running on 64-bit Book 3S processors, specifically POWER7, in hypervisor mode. Using hypervisor mode means that the guest can use the processor's supervisor mode. That means that the guest can execute privileged instructions and access privileged registers itself without trapping to the host. This gives excellent performance, but does mean that KVM cannot emulate a processor architecture other than the one that the hardware implements. This code assumes that the guest is running paravirtualized using the PAPR (Power Architecture Platform Requirements) interface, which is the interface that IBM's PowerVM hypervisor uses. That means that existing Linux distributions that run on IBM pSeries machines will also run under KVM without modification. In order to communicate the PAPR hypercalls to qemu, this adds a new KVM_EXIT_PAPR_HCALL exit code to include/linux/kvm.h. Currently the choice between book3s_hv support and book3s_pr support (i.e. the existing code, which runs the guest in user mode) has to be made at kernel configuration time, so a given kernel binary can only do one or the other. This new book3s_hv code doesn't support MMIO emulation at present. Since we are running paravirtualized guests, this isn't a serious restriction. With the guest running in supervisor mode, most exceptions go straight to the guest. We will never get data or instruction storage or segment interrupts, alignment interrupts, decrementer interrupts, program interrupts, single-step interrupts, etc., coming to the hypervisor from the guest. Therefore this introduces a new KVMTEST_NONHV macro for the exception entry path so that we don't have to do the KVM test on entry to those exception handlers. We do however get hypervisor decrementer, hypervisor data storage, hypervisor instruction storage, and hypervisor emulation assist interrupts, so we have to handle those. In hypervisor mode, real-mode accesses can access all of RAM, not just a limited amount. Therefore we put all the guest state in the vcpu.arch and use the shadow_vcpu in the PACA only for temporary scratch space. We allocate the vcpu with kzalloc rather than vzalloc, and we don't use anything in the kvmppc_vcpu_book3s struct, so we don't allocate it. We don't have a shared page with the guest, but we still need a kvm_vcpu_arch_shared struct to store the values of various registers, so we include one in the vcpu_arch struct. The POWER7 processor has a restriction that all threads in a core have to be in the same partition. MMU-on kernel code counts as a partition (partition 0), so we have to do a partition switch on every entry to and exit from the guest. At present we require the host and guest to run in single-thread mode because of this hardware restriction. This code allocates a hashed page table for the guest and initializes it with HPTEs for the guest's Virtual Real Memory Area (VRMA). We require that the guest memory is allocated using 16MB huge pages, in order to simplify the low-level memory management. This also means that we can get away without tracking paging activity in the host for now, since huge pages can't be paged or swapped. This also adds a few new exports needed by the book3s_hv code. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2011-06-29 08:21:34 +08:00
KVM_HANDLER_PR(PACA_EXGEN, EXC_STD, 0x800)
powerpc: Fix "attempt to move .org backwards" error Building a 64-bit powerpc kernel with PR KVM enabled currently gives this error: AS arch/powerpc/kernel/head_64.o arch/powerpc/kernel/exceptions-64s.S: Assembler messages: arch/powerpc/kernel/exceptions-64s.S:258: Error: attempt to move .org backwards make[2]: *** [arch/powerpc/kernel/head_64.o] Error 1 This happens because the MASKABLE_EXCEPTION_PSERIES macro turns into 33 instructions, but we only have space for 32 at the decrementer interrupt vector (from 0x900 to 0x980). In the code generated by the MASKABLE_EXCEPTION_PSERIES macro, we currently have two instances of the HMT_MEDIUM macro, which has the effect of setting the SMT thread priority to medium. One is the first instruction, and is overwritten by a no-op on processors where we save the PPR (processor priority register), that is, POWER7 or later. The other is after we have saved the PPR. In order to reduce the code at 0x900 by one instruction, we omit the first HMT_MEDIUM. On processors without SMT this will have no effect since HMT_MEDIUM is a no-op there. On POWER5 and RS64 machines this will mean that the first few instructions take a little longer in the case where a decrementer interrupt occurs when the hardware thread is running at low SMT priority. On POWER6 and later machines, the hardware automatically boosts the thread priority when a decrementer interrupt is taken if the thread priority was below medium, so this change won't make any difference. The alternative would be to branch out of line after saving the CFAR. However, that would incur an extra overhead on all processors, whereas the approach adopted here only adds overhead on older threaded processors. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-04-26 01:51:40 +08:00
. = 0x900
.globl decrementer_pSeries
decrementer_pSeries:
_MASKABLE_EXCEPTION_PSERIES(0x900, decrementer, EXC_STD, SOFTEN_TEST_PR)
STD_EXCEPTION_HV(0x980, 0x982, hdecrementer)
MASKABLE_EXCEPTION_PSERIES(0xa00, 0xa00, doorbell_super)
KVM: PPC: Add support for Book3S processors in hypervisor mode This adds support for KVM running on 64-bit Book 3S processors, specifically POWER7, in hypervisor mode. Using hypervisor mode means that the guest can use the processor's supervisor mode. That means that the guest can execute privileged instructions and access privileged registers itself without trapping to the host. This gives excellent performance, but does mean that KVM cannot emulate a processor architecture other than the one that the hardware implements. This code assumes that the guest is running paravirtualized using the PAPR (Power Architecture Platform Requirements) interface, which is the interface that IBM's PowerVM hypervisor uses. That means that existing Linux distributions that run on IBM pSeries machines will also run under KVM without modification. In order to communicate the PAPR hypercalls to qemu, this adds a new KVM_EXIT_PAPR_HCALL exit code to include/linux/kvm.h. Currently the choice between book3s_hv support and book3s_pr support (i.e. the existing code, which runs the guest in user mode) has to be made at kernel configuration time, so a given kernel binary can only do one or the other. This new book3s_hv code doesn't support MMIO emulation at present. Since we are running paravirtualized guests, this isn't a serious restriction. With the guest running in supervisor mode, most exceptions go straight to the guest. We will never get data or instruction storage or segment interrupts, alignment interrupts, decrementer interrupts, program interrupts, single-step interrupts, etc., coming to the hypervisor from the guest. Therefore this introduces a new KVMTEST_NONHV macro for the exception entry path so that we don't have to do the KVM test on entry to those exception handlers. We do however get hypervisor decrementer, hypervisor data storage, hypervisor instruction storage, and hypervisor emulation assist interrupts, so we have to handle those. In hypervisor mode, real-mode accesses can access all of RAM, not just a limited amount. Therefore we put all the guest state in the vcpu.arch and use the shadow_vcpu in the PACA only for temporary scratch space. We allocate the vcpu with kzalloc rather than vzalloc, and we don't use anything in the kvmppc_vcpu_book3s struct, so we don't allocate it. We don't have a shared page with the guest, but we still need a kvm_vcpu_arch_shared struct to store the values of various registers, so we include one in the vcpu_arch struct. The POWER7 processor has a restriction that all threads in a core have to be in the same partition. MMU-on kernel code counts as a partition (partition 0), so we have to do a partition switch on every entry to and exit from the guest. At present we require the host and guest to run in single-thread mode because of this hardware restriction. This code allocates a hashed page table for the guest and initializes it with HPTEs for the guest's Virtual Real Memory Area (VRMA). We require that the guest memory is allocated using 16MB huge pages, in order to simplify the low-level memory management. This also means that we can get away without tracking paging activity in the host for now, since huge pages can't be paged or swapped. This also adds a few new exports needed by the book3s_hv code. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2011-06-29 08:21:34 +08:00
KVM_HANDLER_PR(PACA_EXGEN, EXC_STD, 0xa00)
STD_EXCEPTION_PSERIES(0xb00, 0xb00, trap_0b)
KVM: PPC: Add support for Book3S processors in hypervisor mode This adds support for KVM running on 64-bit Book 3S processors, specifically POWER7, in hypervisor mode. Using hypervisor mode means that the guest can use the processor's supervisor mode. That means that the guest can execute privileged instructions and access privileged registers itself without trapping to the host. This gives excellent performance, but does mean that KVM cannot emulate a processor architecture other than the one that the hardware implements. This code assumes that the guest is running paravirtualized using the PAPR (Power Architecture Platform Requirements) interface, which is the interface that IBM's PowerVM hypervisor uses. That means that existing Linux distributions that run on IBM pSeries machines will also run under KVM without modification. In order to communicate the PAPR hypercalls to qemu, this adds a new KVM_EXIT_PAPR_HCALL exit code to include/linux/kvm.h. Currently the choice between book3s_hv support and book3s_pr support (i.e. the existing code, which runs the guest in user mode) has to be made at kernel configuration time, so a given kernel binary can only do one or the other. This new book3s_hv code doesn't support MMIO emulation at present. Since we are running paravirtualized guests, this isn't a serious restriction. With the guest running in supervisor mode, most exceptions go straight to the guest. We will never get data or instruction storage or segment interrupts, alignment interrupts, decrementer interrupts, program interrupts, single-step interrupts, etc., coming to the hypervisor from the guest. Therefore this introduces a new KVMTEST_NONHV macro for the exception entry path so that we don't have to do the KVM test on entry to those exception handlers. We do however get hypervisor decrementer, hypervisor data storage, hypervisor instruction storage, and hypervisor emulation assist interrupts, so we have to handle those. In hypervisor mode, real-mode accesses can access all of RAM, not just a limited amount. Therefore we put all the guest state in the vcpu.arch and use the shadow_vcpu in the PACA only for temporary scratch space. We allocate the vcpu with kzalloc rather than vzalloc, and we don't use anything in the kvmppc_vcpu_book3s struct, so we don't allocate it. We don't have a shared page with the guest, but we still need a kvm_vcpu_arch_shared struct to store the values of various registers, so we include one in the vcpu_arch struct. The POWER7 processor has a restriction that all threads in a core have to be in the same partition. MMU-on kernel code counts as a partition (partition 0), so we have to do a partition switch on every entry to and exit from the guest. At present we require the host and guest to run in single-thread mode because of this hardware restriction. This code allocates a hashed page table for the guest and initializes it with HPTEs for the guest's Virtual Real Memory Area (VRMA). We require that the guest memory is allocated using 16MB huge pages, in order to simplify the low-level memory management. This also means that we can get away without tracking paging activity in the host for now, since huge pages can't be paged or swapped. This also adds a few new exports needed by the book3s_hv code. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2011-06-29 08:21:34 +08:00
KVM_HANDLER_PR(PACA_EXGEN, EXC_STD, 0xb00)
. = 0xc00
.globl system_call_pSeries
system_call_pSeries:
HMT_MEDIUM
#ifdef CONFIG_KVM_BOOK3S_64_HANDLER
SET_SCRATCH0(r13)
GET_PACA(r13)
std r9,PACA_EXGEN+EX_R9(r13)
std r10,PACA_EXGEN+EX_R10(r13)
mfcr r9
KVMTEST(0xc00)
GET_SCRATCH0(r13)
#endif
SYSCALL_PSERIES_1
SYSCALL_PSERIES_2_RFID
SYSCALL_PSERIES_3
KVM_HANDLER(PACA_EXGEN, EXC_STD, 0xc00)
STD_EXCEPTION_PSERIES(0xd00, 0xd00, single_step)
KVM: PPC: Add support for Book3S processors in hypervisor mode This adds support for KVM running on 64-bit Book 3S processors, specifically POWER7, in hypervisor mode. Using hypervisor mode means that the guest can use the processor's supervisor mode. That means that the guest can execute privileged instructions and access privileged registers itself without trapping to the host. This gives excellent performance, but does mean that KVM cannot emulate a processor architecture other than the one that the hardware implements. This code assumes that the guest is running paravirtualized using the PAPR (Power Architecture Platform Requirements) interface, which is the interface that IBM's PowerVM hypervisor uses. That means that existing Linux distributions that run on IBM pSeries machines will also run under KVM without modification. In order to communicate the PAPR hypercalls to qemu, this adds a new KVM_EXIT_PAPR_HCALL exit code to include/linux/kvm.h. Currently the choice between book3s_hv support and book3s_pr support (i.e. the existing code, which runs the guest in user mode) has to be made at kernel configuration time, so a given kernel binary can only do one or the other. This new book3s_hv code doesn't support MMIO emulation at present. Since we are running paravirtualized guests, this isn't a serious restriction. With the guest running in supervisor mode, most exceptions go straight to the guest. We will never get data or instruction storage or segment interrupts, alignment interrupts, decrementer interrupts, program interrupts, single-step interrupts, etc., coming to the hypervisor from the guest. Therefore this introduces a new KVMTEST_NONHV macro for the exception entry path so that we don't have to do the KVM test on entry to those exception handlers. We do however get hypervisor decrementer, hypervisor data storage, hypervisor instruction storage, and hypervisor emulation assist interrupts, so we have to handle those. In hypervisor mode, real-mode accesses can access all of RAM, not just a limited amount. Therefore we put all the guest state in the vcpu.arch and use the shadow_vcpu in the PACA only for temporary scratch space. We allocate the vcpu with kzalloc rather than vzalloc, and we don't use anything in the kvmppc_vcpu_book3s struct, so we don't allocate it. We don't have a shared page with the guest, but we still need a kvm_vcpu_arch_shared struct to store the values of various registers, so we include one in the vcpu_arch struct. The POWER7 processor has a restriction that all threads in a core have to be in the same partition. MMU-on kernel code counts as a partition (partition 0), so we have to do a partition switch on every entry to and exit from the guest. At present we require the host and guest to run in single-thread mode because of this hardware restriction. This code allocates a hashed page table for the guest and initializes it with HPTEs for the guest's Virtual Real Memory Area (VRMA). We require that the guest memory is allocated using 16MB huge pages, in order to simplify the low-level memory management. This also means that we can get away without tracking paging activity in the host for now, since huge pages can't be paged or swapped. This also adds a few new exports needed by the book3s_hv code. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2011-06-29 08:21:34 +08:00
KVM_HANDLER_PR(PACA_EXGEN, EXC_STD, 0xd00)
/* At 0xe??? we have a bunch of hypervisor exceptions, we branch
* out of line to handle them
*/
. = 0xe00
hv_data_storage_trampoline:
powerpc: Save CFAR before branching in interrupt entry paths Some of the interrupt vectors on 64-bit POWER server processors are only 32 bytes long, which is not enough for the full first-level interrupt handler. For these we currently just have a branch to an out-of-line handler. However, this means that we corrupt the CFAR (come-from address register) on POWER7 and later processors. To fix this, we split the EXCEPTION_PROLOG_1 macro into two pieces: EXCEPTION_PROLOG_0 contains the part up to the point where the CFAR is saved in the PACA, and EXCEPTION_PROLOG_1 contains the rest. We then put EXCEPTION_PROLOG_0 in the short interrupt vectors before we branch to the out-of-line handler, which contains the rest of the first-level interrupt handler. To facilitate this, we define new _OOL (out of line) variants of STD_EXCEPTION_PSERIES, etc. In order to get EXCEPTION_PROLOG_0 to be short enough, i.e., no more than 6 instructions, it was necessary to move the stores that move the PPR and CFAR values into the PACA into __EXCEPTION_PROLOG_1 and to get rid of one of the two HMT_MEDIUM instructions. Previously there was a HMT_MEDIUM_PPR_DISCARD before the prolog, which was nop'd out on processors with the PPR (POWER7 and later), and then another HMT_MEDIUM inside the HMT_MEDIUM_PPR_SAVE macro call inside __EXCEPTION_PROLOG_1, which was nop'd out on processors without PPR. Now the HMT_MEDIUM inside EXCEPTION_PROLOG_0 is there unconditionally and the HMT_MEDIUM_PPR_DISCARD is not strictly necessary, although this leaves it in for the interrupt vectors where there is room for it. Previously we had a handler for hypervisor maintenance interrupts at 0xe50, which doesn't leave enough room for the vector for hypervisor emulation assist interrupts at 0xe40, since we need 8 instructions. The 0xe50 vector was only used on POWER6, as the HMI vector was moved to 0xe60 on POWER7. Since we don't support running in hypervisor mode on POWER6, we just remove the handler at 0xe50. This also changes denorm_exception_hv to use EXCEPTION_PROLOG_0 instead of open-coding it, and removes the HMT_MEDIUM_PPR_DISCARD from the relocation-on vectors (since any CPU that supports relocation-on interrupts also has the PPR). Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-02-05 02:10:15 +08:00
SET_SCRATCH0(r13)
EXCEPTION_PROLOG_0(PACA_EXGEN)
b h_data_storage_hv
powerpc: Save CFAR before branching in interrupt entry paths Some of the interrupt vectors on 64-bit POWER server processors are only 32 bytes long, which is not enough for the full first-level interrupt handler. For these we currently just have a branch to an out-of-line handler. However, this means that we corrupt the CFAR (come-from address register) on POWER7 and later processors. To fix this, we split the EXCEPTION_PROLOG_1 macro into two pieces: EXCEPTION_PROLOG_0 contains the part up to the point where the CFAR is saved in the PACA, and EXCEPTION_PROLOG_1 contains the rest. We then put EXCEPTION_PROLOG_0 in the short interrupt vectors before we branch to the out-of-line handler, which contains the rest of the first-level interrupt handler. To facilitate this, we define new _OOL (out of line) variants of STD_EXCEPTION_PSERIES, etc. In order to get EXCEPTION_PROLOG_0 to be short enough, i.e., no more than 6 instructions, it was necessary to move the stores that move the PPR and CFAR values into the PACA into __EXCEPTION_PROLOG_1 and to get rid of one of the two HMT_MEDIUM instructions. Previously there was a HMT_MEDIUM_PPR_DISCARD before the prolog, which was nop'd out on processors with the PPR (POWER7 and later), and then another HMT_MEDIUM inside the HMT_MEDIUM_PPR_SAVE macro call inside __EXCEPTION_PROLOG_1, which was nop'd out on processors without PPR. Now the HMT_MEDIUM inside EXCEPTION_PROLOG_0 is there unconditionally and the HMT_MEDIUM_PPR_DISCARD is not strictly necessary, although this leaves it in for the interrupt vectors where there is room for it. Previously we had a handler for hypervisor maintenance interrupts at 0xe50, which doesn't leave enough room for the vector for hypervisor emulation assist interrupts at 0xe40, since we need 8 instructions. The 0xe50 vector was only used on POWER6, as the HMI vector was moved to 0xe60 on POWER7. Since we don't support running in hypervisor mode on POWER6, we just remove the handler at 0xe50. This also changes denorm_exception_hv to use EXCEPTION_PROLOG_0 instead of open-coding it, and removes the HMT_MEDIUM_PPR_DISCARD from the relocation-on vectors (since any CPU that supports relocation-on interrupts also has the PPR). Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-02-05 02:10:15 +08:00
. = 0xe20
hv_instr_storage_trampoline:
powerpc: Save CFAR before branching in interrupt entry paths Some of the interrupt vectors on 64-bit POWER server processors are only 32 bytes long, which is not enough for the full first-level interrupt handler. For these we currently just have a branch to an out-of-line handler. However, this means that we corrupt the CFAR (come-from address register) on POWER7 and later processors. To fix this, we split the EXCEPTION_PROLOG_1 macro into two pieces: EXCEPTION_PROLOG_0 contains the part up to the point where the CFAR is saved in the PACA, and EXCEPTION_PROLOG_1 contains the rest. We then put EXCEPTION_PROLOG_0 in the short interrupt vectors before we branch to the out-of-line handler, which contains the rest of the first-level interrupt handler. To facilitate this, we define new _OOL (out of line) variants of STD_EXCEPTION_PSERIES, etc. In order to get EXCEPTION_PROLOG_0 to be short enough, i.e., no more than 6 instructions, it was necessary to move the stores that move the PPR and CFAR values into the PACA into __EXCEPTION_PROLOG_1 and to get rid of one of the two HMT_MEDIUM instructions. Previously there was a HMT_MEDIUM_PPR_DISCARD before the prolog, which was nop'd out on processors with the PPR (POWER7 and later), and then another HMT_MEDIUM inside the HMT_MEDIUM_PPR_SAVE macro call inside __EXCEPTION_PROLOG_1, which was nop'd out on processors without PPR. Now the HMT_MEDIUM inside EXCEPTION_PROLOG_0 is there unconditionally and the HMT_MEDIUM_PPR_DISCARD is not strictly necessary, although this leaves it in for the interrupt vectors where there is room for it. Previously we had a handler for hypervisor maintenance interrupts at 0xe50, which doesn't leave enough room for the vector for hypervisor emulation assist interrupts at 0xe40, since we need 8 instructions. The 0xe50 vector was only used on POWER6, as the HMI vector was moved to 0xe60 on POWER7. Since we don't support running in hypervisor mode on POWER6, we just remove the handler at 0xe50. This also changes denorm_exception_hv to use EXCEPTION_PROLOG_0 instead of open-coding it, and removes the HMT_MEDIUM_PPR_DISCARD from the relocation-on vectors (since any CPU that supports relocation-on interrupts also has the PPR). Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-02-05 02:10:15 +08:00
SET_SCRATCH0(r13)
EXCEPTION_PROLOG_0(PACA_EXGEN)
b h_instr_storage_hv
powerpc: Save CFAR before branching in interrupt entry paths Some of the interrupt vectors on 64-bit POWER server processors are only 32 bytes long, which is not enough for the full first-level interrupt handler. For these we currently just have a branch to an out-of-line handler. However, this means that we corrupt the CFAR (come-from address register) on POWER7 and later processors. To fix this, we split the EXCEPTION_PROLOG_1 macro into two pieces: EXCEPTION_PROLOG_0 contains the part up to the point where the CFAR is saved in the PACA, and EXCEPTION_PROLOG_1 contains the rest. We then put EXCEPTION_PROLOG_0 in the short interrupt vectors before we branch to the out-of-line handler, which contains the rest of the first-level interrupt handler. To facilitate this, we define new _OOL (out of line) variants of STD_EXCEPTION_PSERIES, etc. In order to get EXCEPTION_PROLOG_0 to be short enough, i.e., no more than 6 instructions, it was necessary to move the stores that move the PPR and CFAR values into the PACA into __EXCEPTION_PROLOG_1 and to get rid of one of the two HMT_MEDIUM instructions. Previously there was a HMT_MEDIUM_PPR_DISCARD before the prolog, which was nop'd out on processors with the PPR (POWER7 and later), and then another HMT_MEDIUM inside the HMT_MEDIUM_PPR_SAVE macro call inside __EXCEPTION_PROLOG_1, which was nop'd out on processors without PPR. Now the HMT_MEDIUM inside EXCEPTION_PROLOG_0 is there unconditionally and the HMT_MEDIUM_PPR_DISCARD is not strictly necessary, although this leaves it in for the interrupt vectors where there is room for it. Previously we had a handler for hypervisor maintenance interrupts at 0xe50, which doesn't leave enough room for the vector for hypervisor emulation assist interrupts at 0xe40, since we need 8 instructions. The 0xe50 vector was only used on POWER6, as the HMI vector was moved to 0xe60 on POWER7. Since we don't support running in hypervisor mode on POWER6, we just remove the handler at 0xe50. This also changes denorm_exception_hv to use EXCEPTION_PROLOG_0 instead of open-coding it, and removes the HMT_MEDIUM_PPR_DISCARD from the relocation-on vectors (since any CPU that supports relocation-on interrupts also has the PPR). Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-02-05 02:10:15 +08:00
. = 0xe40
emulation_assist_trampoline:
powerpc: Save CFAR before branching in interrupt entry paths Some of the interrupt vectors on 64-bit POWER server processors are only 32 bytes long, which is not enough for the full first-level interrupt handler. For these we currently just have a branch to an out-of-line handler. However, this means that we corrupt the CFAR (come-from address register) on POWER7 and later processors. To fix this, we split the EXCEPTION_PROLOG_1 macro into two pieces: EXCEPTION_PROLOG_0 contains the part up to the point where the CFAR is saved in the PACA, and EXCEPTION_PROLOG_1 contains the rest. We then put EXCEPTION_PROLOG_0 in the short interrupt vectors before we branch to the out-of-line handler, which contains the rest of the first-level interrupt handler. To facilitate this, we define new _OOL (out of line) variants of STD_EXCEPTION_PSERIES, etc. In order to get EXCEPTION_PROLOG_0 to be short enough, i.e., no more than 6 instructions, it was necessary to move the stores that move the PPR and CFAR values into the PACA into __EXCEPTION_PROLOG_1 and to get rid of one of the two HMT_MEDIUM instructions. Previously there was a HMT_MEDIUM_PPR_DISCARD before the prolog, which was nop'd out on processors with the PPR (POWER7 and later), and then another HMT_MEDIUM inside the HMT_MEDIUM_PPR_SAVE macro call inside __EXCEPTION_PROLOG_1, which was nop'd out on processors without PPR. Now the HMT_MEDIUM inside EXCEPTION_PROLOG_0 is there unconditionally and the HMT_MEDIUM_PPR_DISCARD is not strictly necessary, although this leaves it in for the interrupt vectors where there is room for it. Previously we had a handler for hypervisor maintenance interrupts at 0xe50, which doesn't leave enough room for the vector for hypervisor emulation assist interrupts at 0xe40, since we need 8 instructions. The 0xe50 vector was only used on POWER6, as the HMI vector was moved to 0xe60 on POWER7. Since we don't support running in hypervisor mode on POWER6, we just remove the handler at 0xe50. This also changes denorm_exception_hv to use EXCEPTION_PROLOG_0 instead of open-coding it, and removes the HMT_MEDIUM_PPR_DISCARD from the relocation-on vectors (since any CPU that supports relocation-on interrupts also has the PPR). Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-02-05 02:10:15 +08:00
SET_SCRATCH0(r13)
EXCEPTION_PROLOG_0(PACA_EXGEN)
b emulation_assist_hv
powerpc: Save CFAR before branching in interrupt entry paths Some of the interrupt vectors on 64-bit POWER server processors are only 32 bytes long, which is not enough for the full first-level interrupt handler. For these we currently just have a branch to an out-of-line handler. However, this means that we corrupt the CFAR (come-from address register) on POWER7 and later processors. To fix this, we split the EXCEPTION_PROLOG_1 macro into two pieces: EXCEPTION_PROLOG_0 contains the part up to the point where the CFAR is saved in the PACA, and EXCEPTION_PROLOG_1 contains the rest. We then put EXCEPTION_PROLOG_0 in the short interrupt vectors before we branch to the out-of-line handler, which contains the rest of the first-level interrupt handler. To facilitate this, we define new _OOL (out of line) variants of STD_EXCEPTION_PSERIES, etc. In order to get EXCEPTION_PROLOG_0 to be short enough, i.e., no more than 6 instructions, it was necessary to move the stores that move the PPR and CFAR values into the PACA into __EXCEPTION_PROLOG_1 and to get rid of one of the two HMT_MEDIUM instructions. Previously there was a HMT_MEDIUM_PPR_DISCARD before the prolog, which was nop'd out on processors with the PPR (POWER7 and later), and then another HMT_MEDIUM inside the HMT_MEDIUM_PPR_SAVE macro call inside __EXCEPTION_PROLOG_1, which was nop'd out on processors without PPR. Now the HMT_MEDIUM inside EXCEPTION_PROLOG_0 is there unconditionally and the HMT_MEDIUM_PPR_DISCARD is not strictly necessary, although this leaves it in for the interrupt vectors where there is room for it. Previously we had a handler for hypervisor maintenance interrupts at 0xe50, which doesn't leave enough room for the vector for hypervisor emulation assist interrupts at 0xe40, since we need 8 instructions. The 0xe50 vector was only used on POWER6, as the HMI vector was moved to 0xe60 on POWER7. Since we don't support running in hypervisor mode on POWER6, we just remove the handler at 0xe50. This also changes denorm_exception_hv to use EXCEPTION_PROLOG_0 instead of open-coding it, and removes the HMT_MEDIUM_PPR_DISCARD from the relocation-on vectors (since any CPU that supports relocation-on interrupts also has the PPR). Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-02-05 02:10:15 +08:00
. = 0xe60
hv_exception_trampoline:
powerpc: Save CFAR before branching in interrupt entry paths Some of the interrupt vectors on 64-bit POWER server processors are only 32 bytes long, which is not enough for the full first-level interrupt handler. For these we currently just have a branch to an out-of-line handler. However, this means that we corrupt the CFAR (come-from address register) on POWER7 and later processors. To fix this, we split the EXCEPTION_PROLOG_1 macro into two pieces: EXCEPTION_PROLOG_0 contains the part up to the point where the CFAR is saved in the PACA, and EXCEPTION_PROLOG_1 contains the rest. We then put EXCEPTION_PROLOG_0 in the short interrupt vectors before we branch to the out-of-line handler, which contains the rest of the first-level interrupt handler. To facilitate this, we define new _OOL (out of line) variants of STD_EXCEPTION_PSERIES, etc. In order to get EXCEPTION_PROLOG_0 to be short enough, i.e., no more than 6 instructions, it was necessary to move the stores that move the PPR and CFAR values into the PACA into __EXCEPTION_PROLOG_1 and to get rid of one of the two HMT_MEDIUM instructions. Previously there was a HMT_MEDIUM_PPR_DISCARD before the prolog, which was nop'd out on processors with the PPR (POWER7 and later), and then another HMT_MEDIUM inside the HMT_MEDIUM_PPR_SAVE macro call inside __EXCEPTION_PROLOG_1, which was nop'd out on processors without PPR. Now the HMT_MEDIUM inside EXCEPTION_PROLOG_0 is there unconditionally and the HMT_MEDIUM_PPR_DISCARD is not strictly necessary, although this leaves it in for the interrupt vectors where there is room for it. Previously we had a handler for hypervisor maintenance interrupts at 0xe50, which doesn't leave enough room for the vector for hypervisor emulation assist interrupts at 0xe40, since we need 8 instructions. The 0xe50 vector was only used on POWER6, as the HMI vector was moved to 0xe60 on POWER7. Since we don't support running in hypervisor mode on POWER6, we just remove the handler at 0xe50. This also changes denorm_exception_hv to use EXCEPTION_PROLOG_0 instead of open-coding it, and removes the HMT_MEDIUM_PPR_DISCARD from the relocation-on vectors (since any CPU that supports relocation-on interrupts also has the PPR). Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-02-05 02:10:15 +08:00
SET_SCRATCH0(r13)
EXCEPTION_PROLOG_0(PACA_EXGEN)
b hmi_exception_early
powerpc: Save CFAR before branching in interrupt entry paths Some of the interrupt vectors on 64-bit POWER server processors are only 32 bytes long, which is not enough for the full first-level interrupt handler. For these we currently just have a branch to an out-of-line handler. However, this means that we corrupt the CFAR (come-from address register) on POWER7 and later processors. To fix this, we split the EXCEPTION_PROLOG_1 macro into two pieces: EXCEPTION_PROLOG_0 contains the part up to the point where the CFAR is saved in the PACA, and EXCEPTION_PROLOG_1 contains the rest. We then put EXCEPTION_PROLOG_0 in the short interrupt vectors before we branch to the out-of-line handler, which contains the rest of the first-level interrupt handler. To facilitate this, we define new _OOL (out of line) variants of STD_EXCEPTION_PSERIES, etc. In order to get EXCEPTION_PROLOG_0 to be short enough, i.e., no more than 6 instructions, it was necessary to move the stores that move the PPR and CFAR values into the PACA into __EXCEPTION_PROLOG_1 and to get rid of one of the two HMT_MEDIUM instructions. Previously there was a HMT_MEDIUM_PPR_DISCARD before the prolog, which was nop'd out on processors with the PPR (POWER7 and later), and then another HMT_MEDIUM inside the HMT_MEDIUM_PPR_SAVE macro call inside __EXCEPTION_PROLOG_1, which was nop'd out on processors without PPR. Now the HMT_MEDIUM inside EXCEPTION_PROLOG_0 is there unconditionally and the HMT_MEDIUM_PPR_DISCARD is not strictly necessary, although this leaves it in for the interrupt vectors where there is room for it. Previously we had a handler for hypervisor maintenance interrupts at 0xe50, which doesn't leave enough room for the vector for hypervisor emulation assist interrupts at 0xe40, since we need 8 instructions. The 0xe50 vector was only used on POWER6, as the HMI vector was moved to 0xe60 on POWER7. Since we don't support running in hypervisor mode on POWER6, we just remove the handler at 0xe50. This also changes denorm_exception_hv to use EXCEPTION_PROLOG_0 instead of open-coding it, and removes the HMT_MEDIUM_PPR_DISCARD from the relocation-on vectors (since any CPU that supports relocation-on interrupts also has the PPR). Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-02-05 02:10:15 +08:00
. = 0xe80
hv_doorbell_trampoline:
powerpc: Save CFAR before branching in interrupt entry paths Some of the interrupt vectors on 64-bit POWER server processors are only 32 bytes long, which is not enough for the full first-level interrupt handler. For these we currently just have a branch to an out-of-line handler. However, this means that we corrupt the CFAR (come-from address register) on POWER7 and later processors. To fix this, we split the EXCEPTION_PROLOG_1 macro into two pieces: EXCEPTION_PROLOG_0 contains the part up to the point where the CFAR is saved in the PACA, and EXCEPTION_PROLOG_1 contains the rest. We then put EXCEPTION_PROLOG_0 in the short interrupt vectors before we branch to the out-of-line handler, which contains the rest of the first-level interrupt handler. To facilitate this, we define new _OOL (out of line) variants of STD_EXCEPTION_PSERIES, etc. In order to get EXCEPTION_PROLOG_0 to be short enough, i.e., no more than 6 instructions, it was necessary to move the stores that move the PPR and CFAR values into the PACA into __EXCEPTION_PROLOG_1 and to get rid of one of the two HMT_MEDIUM instructions. Previously there was a HMT_MEDIUM_PPR_DISCARD before the prolog, which was nop'd out on processors with the PPR (POWER7 and later), and then another HMT_MEDIUM inside the HMT_MEDIUM_PPR_SAVE macro call inside __EXCEPTION_PROLOG_1, which was nop'd out on processors without PPR. Now the HMT_MEDIUM inside EXCEPTION_PROLOG_0 is there unconditionally and the HMT_MEDIUM_PPR_DISCARD is not strictly necessary, although this leaves it in for the interrupt vectors where there is room for it. Previously we had a handler for hypervisor maintenance interrupts at 0xe50, which doesn't leave enough room for the vector for hypervisor emulation assist interrupts at 0xe40, since we need 8 instructions. The 0xe50 vector was only used on POWER6, as the HMI vector was moved to 0xe60 on POWER7. Since we don't support running in hypervisor mode on POWER6, we just remove the handler at 0xe50. This also changes denorm_exception_hv to use EXCEPTION_PROLOG_0 instead of open-coding it, and removes the HMT_MEDIUM_PPR_DISCARD from the relocation-on vectors (since any CPU that supports relocation-on interrupts also has the PPR). Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-02-05 02:10:15 +08:00
SET_SCRATCH0(r13)
EXCEPTION_PROLOG_0(PACA_EXGEN)
b h_doorbell_hv
/* We need to deal with the Altivec unavailable exception
* here which is at 0xf20, thus in the middle of the
* prolog code of the PerformanceMonitor one. A little
* trickery is thus necessary
*/
. = 0xf00
performance_monitor_pseries_trampoline:
powerpc: Save CFAR before branching in interrupt entry paths Some of the interrupt vectors on 64-bit POWER server processors are only 32 bytes long, which is not enough for the full first-level interrupt handler. For these we currently just have a branch to an out-of-line handler. However, this means that we corrupt the CFAR (come-from address register) on POWER7 and later processors. To fix this, we split the EXCEPTION_PROLOG_1 macro into two pieces: EXCEPTION_PROLOG_0 contains the part up to the point where the CFAR is saved in the PACA, and EXCEPTION_PROLOG_1 contains the rest. We then put EXCEPTION_PROLOG_0 in the short interrupt vectors before we branch to the out-of-line handler, which contains the rest of the first-level interrupt handler. To facilitate this, we define new _OOL (out of line) variants of STD_EXCEPTION_PSERIES, etc. In order to get EXCEPTION_PROLOG_0 to be short enough, i.e., no more than 6 instructions, it was necessary to move the stores that move the PPR and CFAR values into the PACA into __EXCEPTION_PROLOG_1 and to get rid of one of the two HMT_MEDIUM instructions. Previously there was a HMT_MEDIUM_PPR_DISCARD before the prolog, which was nop'd out on processors with the PPR (POWER7 and later), and then another HMT_MEDIUM inside the HMT_MEDIUM_PPR_SAVE macro call inside __EXCEPTION_PROLOG_1, which was nop'd out on processors without PPR. Now the HMT_MEDIUM inside EXCEPTION_PROLOG_0 is there unconditionally and the HMT_MEDIUM_PPR_DISCARD is not strictly necessary, although this leaves it in for the interrupt vectors where there is room for it. Previously we had a handler for hypervisor maintenance interrupts at 0xe50, which doesn't leave enough room for the vector for hypervisor emulation assist interrupts at 0xe40, since we need 8 instructions. The 0xe50 vector was only used on POWER6, as the HMI vector was moved to 0xe60 on POWER7. Since we don't support running in hypervisor mode on POWER6, we just remove the handler at 0xe50. This also changes denorm_exception_hv to use EXCEPTION_PROLOG_0 instead of open-coding it, and removes the HMT_MEDIUM_PPR_DISCARD from the relocation-on vectors (since any CPU that supports relocation-on interrupts also has the PPR). Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-02-05 02:10:15 +08:00
SET_SCRATCH0(r13)
EXCEPTION_PROLOG_0(PACA_EXGEN)
b performance_monitor_pSeries
. = 0xf20
altivec_unavailable_pseries_trampoline:
powerpc: Save CFAR before branching in interrupt entry paths Some of the interrupt vectors on 64-bit POWER server processors are only 32 bytes long, which is not enough for the full first-level interrupt handler. For these we currently just have a branch to an out-of-line handler. However, this means that we corrupt the CFAR (come-from address register) on POWER7 and later processors. To fix this, we split the EXCEPTION_PROLOG_1 macro into two pieces: EXCEPTION_PROLOG_0 contains the part up to the point where the CFAR is saved in the PACA, and EXCEPTION_PROLOG_1 contains the rest. We then put EXCEPTION_PROLOG_0 in the short interrupt vectors before we branch to the out-of-line handler, which contains the rest of the first-level interrupt handler. To facilitate this, we define new _OOL (out of line) variants of STD_EXCEPTION_PSERIES, etc. In order to get EXCEPTION_PROLOG_0 to be short enough, i.e., no more than 6 instructions, it was necessary to move the stores that move the PPR and CFAR values into the PACA into __EXCEPTION_PROLOG_1 and to get rid of one of the two HMT_MEDIUM instructions. Previously there was a HMT_MEDIUM_PPR_DISCARD before the prolog, which was nop'd out on processors with the PPR (POWER7 and later), and then another HMT_MEDIUM inside the HMT_MEDIUM_PPR_SAVE macro call inside __EXCEPTION_PROLOG_1, which was nop'd out on processors without PPR. Now the HMT_MEDIUM inside EXCEPTION_PROLOG_0 is there unconditionally and the HMT_MEDIUM_PPR_DISCARD is not strictly necessary, although this leaves it in for the interrupt vectors where there is room for it. Previously we had a handler for hypervisor maintenance interrupts at 0xe50, which doesn't leave enough room for the vector for hypervisor emulation assist interrupts at 0xe40, since we need 8 instructions. The 0xe50 vector was only used on POWER6, as the HMI vector was moved to 0xe60 on POWER7. Since we don't support running in hypervisor mode on POWER6, we just remove the handler at 0xe50. This also changes denorm_exception_hv to use EXCEPTION_PROLOG_0 instead of open-coding it, and removes the HMT_MEDIUM_PPR_DISCARD from the relocation-on vectors (since any CPU that supports relocation-on interrupts also has the PPR). Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-02-05 02:10:15 +08:00
SET_SCRATCH0(r13)
EXCEPTION_PROLOG_0(PACA_EXGEN)
b altivec_unavailable_pSeries
. = 0xf40
vsx_unavailable_pseries_trampoline:
powerpc: Save CFAR before branching in interrupt entry paths Some of the interrupt vectors on 64-bit POWER server processors are only 32 bytes long, which is not enough for the full first-level interrupt handler. For these we currently just have a branch to an out-of-line handler. However, this means that we corrupt the CFAR (come-from address register) on POWER7 and later processors. To fix this, we split the EXCEPTION_PROLOG_1 macro into two pieces: EXCEPTION_PROLOG_0 contains the part up to the point where the CFAR is saved in the PACA, and EXCEPTION_PROLOG_1 contains the rest. We then put EXCEPTION_PROLOG_0 in the short interrupt vectors before we branch to the out-of-line handler, which contains the rest of the first-level interrupt handler. To facilitate this, we define new _OOL (out of line) variants of STD_EXCEPTION_PSERIES, etc. In order to get EXCEPTION_PROLOG_0 to be short enough, i.e., no more than 6 instructions, it was necessary to move the stores that move the PPR and CFAR values into the PACA into __EXCEPTION_PROLOG_1 and to get rid of one of the two HMT_MEDIUM instructions. Previously there was a HMT_MEDIUM_PPR_DISCARD before the prolog, which was nop'd out on processors with the PPR (POWER7 and later), and then another HMT_MEDIUM inside the HMT_MEDIUM_PPR_SAVE macro call inside __EXCEPTION_PROLOG_1, which was nop'd out on processors without PPR. Now the HMT_MEDIUM inside EXCEPTION_PROLOG_0 is there unconditionally and the HMT_MEDIUM_PPR_DISCARD is not strictly necessary, although this leaves it in for the interrupt vectors where there is room for it. Previously we had a handler for hypervisor maintenance interrupts at 0xe50, which doesn't leave enough room for the vector for hypervisor emulation assist interrupts at 0xe40, since we need 8 instructions. The 0xe50 vector was only used on POWER6, as the HMI vector was moved to 0xe60 on POWER7. Since we don't support running in hypervisor mode on POWER6, we just remove the handler at 0xe50. This also changes denorm_exception_hv to use EXCEPTION_PROLOG_0 instead of open-coding it, and removes the HMT_MEDIUM_PPR_DISCARD from the relocation-on vectors (since any CPU that supports relocation-on interrupts also has the PPR). Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-02-05 02:10:15 +08:00
SET_SCRATCH0(r13)
EXCEPTION_PROLOG_0(PACA_EXGEN)
b vsx_unavailable_pSeries
. = 0xf60
facility_unavailable_trampoline:
SET_SCRATCH0(r13)
EXCEPTION_PROLOG_0(PACA_EXGEN)
b facility_unavailable_pSeries
. = 0xf80
hv_facility_unavailable_trampoline:
SET_SCRATCH0(r13)
EXCEPTION_PROLOG_0(PACA_EXGEN)
b facility_unavailable_hv
#ifdef CONFIG_CBE_RAS
STD_EXCEPTION_HV(0x1200, 0x1202, cbe_system_error)
KVM_HANDLER_SKIP(PACA_EXGEN, EXC_HV, 0x1202)
#endif /* CONFIG_CBE_RAS */
STD_EXCEPTION_PSERIES(0x1300, 0x1300, instruction_breakpoint)
KVM: PPC: Add support for Book3S processors in hypervisor mode This adds support for KVM running on 64-bit Book 3S processors, specifically POWER7, in hypervisor mode. Using hypervisor mode means that the guest can use the processor's supervisor mode. That means that the guest can execute privileged instructions and access privileged registers itself without trapping to the host. This gives excellent performance, but does mean that KVM cannot emulate a processor architecture other than the one that the hardware implements. This code assumes that the guest is running paravirtualized using the PAPR (Power Architecture Platform Requirements) interface, which is the interface that IBM's PowerVM hypervisor uses. That means that existing Linux distributions that run on IBM pSeries machines will also run under KVM without modification. In order to communicate the PAPR hypercalls to qemu, this adds a new KVM_EXIT_PAPR_HCALL exit code to include/linux/kvm.h. Currently the choice between book3s_hv support and book3s_pr support (i.e. the existing code, which runs the guest in user mode) has to be made at kernel configuration time, so a given kernel binary can only do one or the other. This new book3s_hv code doesn't support MMIO emulation at present. Since we are running paravirtualized guests, this isn't a serious restriction. With the guest running in supervisor mode, most exceptions go straight to the guest. We will never get data or instruction storage or segment interrupts, alignment interrupts, decrementer interrupts, program interrupts, single-step interrupts, etc., coming to the hypervisor from the guest. Therefore this introduces a new KVMTEST_NONHV macro for the exception entry path so that we don't have to do the KVM test on entry to those exception handlers. We do however get hypervisor decrementer, hypervisor data storage, hypervisor instruction storage, and hypervisor emulation assist interrupts, so we have to handle those. In hypervisor mode, real-mode accesses can access all of RAM, not just a limited amount. Therefore we put all the guest state in the vcpu.arch and use the shadow_vcpu in the PACA only for temporary scratch space. We allocate the vcpu with kzalloc rather than vzalloc, and we don't use anything in the kvmppc_vcpu_book3s struct, so we don't allocate it. We don't have a shared page with the guest, but we still need a kvm_vcpu_arch_shared struct to store the values of various registers, so we include one in the vcpu_arch struct. The POWER7 processor has a restriction that all threads in a core have to be in the same partition. MMU-on kernel code counts as a partition (partition 0), so we have to do a partition switch on every entry to and exit from the guest. At present we require the host and guest to run in single-thread mode because of this hardware restriction. This code allocates a hashed page table for the guest and initializes it with HPTEs for the guest's Virtual Real Memory Area (VRMA). We require that the guest memory is allocated using 16MB huge pages, in order to simplify the low-level memory management. This also means that we can get away without tracking paging activity in the host for now, since huge pages can't be paged or swapped. This also adds a few new exports needed by the book3s_hv code. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2011-06-29 08:21:34 +08:00
KVM_HANDLER_PR_SKIP(PACA_EXGEN, EXC_STD, 0x1300)
. = 0x1500
.global denorm_exception_hv
denorm_exception_hv:
HMT_MEDIUM_PPR_DISCARD
mtspr SPRN_SPRG_HSCRATCH0,r13
powerpc: Save CFAR before branching in interrupt entry paths Some of the interrupt vectors on 64-bit POWER server processors are only 32 bytes long, which is not enough for the full first-level interrupt handler. For these we currently just have a branch to an out-of-line handler. However, this means that we corrupt the CFAR (come-from address register) on POWER7 and later processors. To fix this, we split the EXCEPTION_PROLOG_1 macro into two pieces: EXCEPTION_PROLOG_0 contains the part up to the point where the CFAR is saved in the PACA, and EXCEPTION_PROLOG_1 contains the rest. We then put EXCEPTION_PROLOG_0 in the short interrupt vectors before we branch to the out-of-line handler, which contains the rest of the first-level interrupt handler. To facilitate this, we define new _OOL (out of line) variants of STD_EXCEPTION_PSERIES, etc. In order to get EXCEPTION_PROLOG_0 to be short enough, i.e., no more than 6 instructions, it was necessary to move the stores that move the PPR and CFAR values into the PACA into __EXCEPTION_PROLOG_1 and to get rid of one of the two HMT_MEDIUM instructions. Previously there was a HMT_MEDIUM_PPR_DISCARD before the prolog, which was nop'd out on processors with the PPR (POWER7 and later), and then another HMT_MEDIUM inside the HMT_MEDIUM_PPR_SAVE macro call inside __EXCEPTION_PROLOG_1, which was nop'd out on processors without PPR. Now the HMT_MEDIUM inside EXCEPTION_PROLOG_0 is there unconditionally and the HMT_MEDIUM_PPR_DISCARD is not strictly necessary, although this leaves it in for the interrupt vectors where there is room for it. Previously we had a handler for hypervisor maintenance interrupts at 0xe50, which doesn't leave enough room for the vector for hypervisor emulation assist interrupts at 0xe40, since we need 8 instructions. The 0xe50 vector was only used on POWER6, as the HMI vector was moved to 0xe60 on POWER7. Since we don't support running in hypervisor mode on POWER6, we just remove the handler at 0xe50. This also changes denorm_exception_hv to use EXCEPTION_PROLOG_0 instead of open-coding it, and removes the HMT_MEDIUM_PPR_DISCARD from the relocation-on vectors (since any CPU that supports relocation-on interrupts also has the PPR). Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-02-05 02:10:15 +08:00
EXCEPTION_PROLOG_0(PACA_EXGEN)
EXCEPTION_PROLOG_1(PACA_EXGEN, NOTEST, 0x1500)
#ifdef CONFIG_PPC_DENORMALISATION
mfspr r10,SPRN_HSRR1
mfspr r11,SPRN_HSRR0 /* save HSRR0 */
andis. r10,r10,(HSRR1_DENORM)@h /* denorm? */
addi r11,r11,-4 /* HSRR0 is next instruction */
bne+ denorm_assist
#endif
KVMTEST(0x1500)
EXCEPTION_PROLOG_PSERIES_1(denorm_common, EXC_HV)
KVM_HANDLER_SKIP(PACA_EXGEN, EXC_STD, 0x1500)
#ifdef CONFIG_CBE_RAS
STD_EXCEPTION_HV(0x1600, 0x1602, cbe_maintenance)
KVM_HANDLER_SKIP(PACA_EXGEN, EXC_HV, 0x1602)
#endif /* CONFIG_CBE_RAS */
STD_EXCEPTION_PSERIES(0x1700, 0x1700, altivec_assist)
KVM: PPC: Add support for Book3S processors in hypervisor mode This adds support for KVM running on 64-bit Book 3S processors, specifically POWER7, in hypervisor mode. Using hypervisor mode means that the guest can use the processor's supervisor mode. That means that the guest can execute privileged instructions and access privileged registers itself without trapping to the host. This gives excellent performance, but does mean that KVM cannot emulate a processor architecture other than the one that the hardware implements. This code assumes that the guest is running paravirtualized using the PAPR (Power Architecture Platform Requirements) interface, which is the interface that IBM's PowerVM hypervisor uses. That means that existing Linux distributions that run on IBM pSeries machines will also run under KVM without modification. In order to communicate the PAPR hypercalls to qemu, this adds a new KVM_EXIT_PAPR_HCALL exit code to include/linux/kvm.h. Currently the choice between book3s_hv support and book3s_pr support (i.e. the existing code, which runs the guest in user mode) has to be made at kernel configuration time, so a given kernel binary can only do one or the other. This new book3s_hv code doesn't support MMIO emulation at present. Since we are running paravirtualized guests, this isn't a serious restriction. With the guest running in supervisor mode, most exceptions go straight to the guest. We will never get data or instruction storage or segment interrupts, alignment interrupts, decrementer interrupts, program interrupts, single-step interrupts, etc., coming to the hypervisor from the guest. Therefore this introduces a new KVMTEST_NONHV macro for the exception entry path so that we don't have to do the KVM test on entry to those exception handlers. We do however get hypervisor decrementer, hypervisor data storage, hypervisor instruction storage, and hypervisor emulation assist interrupts, so we have to handle those. In hypervisor mode, real-mode accesses can access all of RAM, not just a limited amount. Therefore we put all the guest state in the vcpu.arch and use the shadow_vcpu in the PACA only for temporary scratch space. We allocate the vcpu with kzalloc rather than vzalloc, and we don't use anything in the kvmppc_vcpu_book3s struct, so we don't allocate it. We don't have a shared page with the guest, but we still need a kvm_vcpu_arch_shared struct to store the values of various registers, so we include one in the vcpu_arch struct. The POWER7 processor has a restriction that all threads in a core have to be in the same partition. MMU-on kernel code counts as a partition (partition 0), so we have to do a partition switch on every entry to and exit from the guest. At present we require the host and guest to run in single-thread mode because of this hardware restriction. This code allocates a hashed page table for the guest and initializes it with HPTEs for the guest's Virtual Real Memory Area (VRMA). We require that the guest memory is allocated using 16MB huge pages, in order to simplify the low-level memory management. This also means that we can get away without tracking paging activity in the host for now, since huge pages can't be paged or swapped. This also adds a few new exports needed by the book3s_hv code. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2011-06-29 08:21:34 +08:00
KVM_HANDLER_PR(PACA_EXGEN, EXC_STD, 0x1700)
#ifdef CONFIG_CBE_RAS
STD_EXCEPTION_HV(0x1800, 0x1802, cbe_thermal)
KVM_HANDLER_SKIP(PACA_EXGEN, EXC_HV, 0x1802)
#else
. = 0x1800
#endif /* CONFIG_CBE_RAS */
/*** Out of line interrupts support ***/
.align 7
/* moved from 0x200 */
powerpc/book3s: handle machine check in Linux host. Move machine check entry point into Linux. So far we were dependent on firmware to decode MCE error details and handover the high level info to OS. This patch introduces early machine check routine that saves the MCE information (srr1, srr0, dar and dsisr) to the emergency stack. We allocate stack frame on emergency stack and set the r1 accordingly. This allows us to be prepared to take another exception without loosing context. One thing to note here that, if we get another machine check while ME bit is off then we risk a checkstop. Hence we restrict ourselves to save only MCE information and register saved on PACA_EXMC save are before we turn the ME bit on. We use paca->in_mce flag to differentiate between first entry and nested machine check entry which helps proper use of emergency stack. We increment paca->in_mce every time we enter in early machine check handler and decrement it while leaving. When we enter machine check early handler first time (paca->in_mce == 0), we are sure nobody is using MC emergency stack and allocate a stack frame at the start of the emergency stack. During subsequent entry (paca->in_mce > 0), we know that r1 points inside emergency stack and we allocate separate stack frame accordingly. This prevents us from clobbering MCE information during nested machine checks. The early machine check handler changes are placed under CPU_FTR_HVMODE section. This makes sure that the early machine check handler will get executed only in hypervisor kernel. This is the code flow: Machine Check Interrupt | V 0x200 vector ME=0, IR=0, DR=0 | V +-----------------------------------------------+ |machine_check_pSeries_early: | ME=0, IR=0, DR=0 | Alloc frame on emergency stack | | Save srr1, srr0, dar and dsisr on stack | +-----------------------------------------------+ | (ME=1, IR=0, DR=0, RFID) | V machine_check_handle_early ME=1, IR=0, DR=0 | V +-----------------------------------------------+ | machine_check_early (r3=pt_regs) | ME=1, IR=0, DR=0 | Things to do: (in next patches) | | Flush SLB for SLB errors | | Flush TLB for TLB errors | | Decode and save MCE info | +-----------------------------------------------+ | (Fall through existing exception handler routine.) | V machine_check_pSerie ME=1, IR=0, DR=0 | (ME=1, IR=1, DR=1, RFID) | V machine_check_common ME=1, IR=1, DR=1 . . . Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-10-30 22:34:08 +08:00
machine_check_pSeries_early:
BEGIN_FTR_SECTION
EXCEPTION_PROLOG_1(PACA_EXMC, NOTEST, 0x200)
/*
* Register contents:
* R13 = PACA
* R9 = CR
* Original R9 to R13 is saved on PACA_EXMC
*
* Switch to mc_emergency stack and handle re-entrancy (we limit
* the nested MCE upto level 4 to avoid stack overflow).
* Save MCE registers srr1, srr0, dar and dsisr and then set ME=1
powerpc/book3s: handle machine check in Linux host. Move machine check entry point into Linux. So far we were dependent on firmware to decode MCE error details and handover the high level info to OS. This patch introduces early machine check routine that saves the MCE information (srr1, srr0, dar and dsisr) to the emergency stack. We allocate stack frame on emergency stack and set the r1 accordingly. This allows us to be prepared to take another exception without loosing context. One thing to note here that, if we get another machine check while ME bit is off then we risk a checkstop. Hence we restrict ourselves to save only MCE information and register saved on PACA_EXMC save are before we turn the ME bit on. We use paca->in_mce flag to differentiate between first entry and nested machine check entry which helps proper use of emergency stack. We increment paca->in_mce every time we enter in early machine check handler and decrement it while leaving. When we enter machine check early handler first time (paca->in_mce == 0), we are sure nobody is using MC emergency stack and allocate a stack frame at the start of the emergency stack. During subsequent entry (paca->in_mce > 0), we know that r1 points inside emergency stack and we allocate separate stack frame accordingly. This prevents us from clobbering MCE information during nested machine checks. The early machine check handler changes are placed under CPU_FTR_HVMODE section. This makes sure that the early machine check handler will get executed only in hypervisor kernel. This is the code flow: Machine Check Interrupt | V 0x200 vector ME=0, IR=0, DR=0 | V +-----------------------------------------------+ |machine_check_pSeries_early: | ME=0, IR=0, DR=0 | Alloc frame on emergency stack | | Save srr1, srr0, dar and dsisr on stack | +-----------------------------------------------+ | (ME=1, IR=0, DR=0, RFID) | V machine_check_handle_early ME=1, IR=0, DR=0 | V +-----------------------------------------------+ | machine_check_early (r3=pt_regs) | ME=1, IR=0, DR=0 | Things to do: (in next patches) | | Flush SLB for SLB errors | | Flush TLB for TLB errors | | Decode and save MCE info | +-----------------------------------------------+ | (Fall through existing exception handler routine.) | V machine_check_pSerie ME=1, IR=0, DR=0 | (ME=1, IR=1, DR=1, RFID) | V machine_check_common ME=1, IR=1, DR=1 . . . Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-10-30 22:34:08 +08:00
*
* We use paca->in_mce to check whether this is the first entry or
* nested machine check. We increment paca->in_mce to track nested
* machine checks.
*
* If this is the first entry then set stack pointer to
* paca->mc_emergency_sp, otherwise r1 is already pointing to
* stack frame on mc_emergency stack.
*
* NOTE: We are here with MSR_ME=0 (off), which means we risk a
* checkstop if we get another machine check exception before we do
* rfid with MSR_ME=1.
*/
mr r11,r1 /* Save r1 */
lhz r10,PACA_IN_MCE(r13)
cmpwi r10,0 /* Are we in nested machine check */
bne 0f /* Yes, we are. */
/* First machine check entry */
ld r1,PACAMCEMERGSP(r13) /* Use MC emergency stack */
0: subi r1,r1,INT_FRAME_SIZE /* alloc stack frame */
addi r10,r10,1 /* increment paca->in_mce */
sth r10,PACA_IN_MCE(r13)
/* Limit nested MCE to level 4 to avoid stack overflow */
cmpwi r10,4
bgt 2f /* Check if we hit limit of 4 */
powerpc/book3s: handle machine check in Linux host. Move machine check entry point into Linux. So far we were dependent on firmware to decode MCE error details and handover the high level info to OS. This patch introduces early machine check routine that saves the MCE information (srr1, srr0, dar and dsisr) to the emergency stack. We allocate stack frame on emergency stack and set the r1 accordingly. This allows us to be prepared to take another exception without loosing context. One thing to note here that, if we get another machine check while ME bit is off then we risk a checkstop. Hence we restrict ourselves to save only MCE information and register saved on PACA_EXMC save are before we turn the ME bit on. We use paca->in_mce flag to differentiate between first entry and nested machine check entry which helps proper use of emergency stack. We increment paca->in_mce every time we enter in early machine check handler and decrement it while leaving. When we enter machine check early handler first time (paca->in_mce == 0), we are sure nobody is using MC emergency stack and allocate a stack frame at the start of the emergency stack. During subsequent entry (paca->in_mce > 0), we know that r1 points inside emergency stack and we allocate separate stack frame accordingly. This prevents us from clobbering MCE information during nested machine checks. The early machine check handler changes are placed under CPU_FTR_HVMODE section. This makes sure that the early machine check handler will get executed only in hypervisor kernel. This is the code flow: Machine Check Interrupt | V 0x200 vector ME=0, IR=0, DR=0 | V +-----------------------------------------------+ |machine_check_pSeries_early: | ME=0, IR=0, DR=0 | Alloc frame on emergency stack | | Save srr1, srr0, dar and dsisr on stack | +-----------------------------------------------+ | (ME=1, IR=0, DR=0, RFID) | V machine_check_handle_early ME=1, IR=0, DR=0 | V +-----------------------------------------------+ | machine_check_early (r3=pt_regs) | ME=1, IR=0, DR=0 | Things to do: (in next patches) | | Flush SLB for SLB errors | | Flush TLB for TLB errors | | Decode and save MCE info | +-----------------------------------------------+ | (Fall through existing exception handler routine.) | V machine_check_pSerie ME=1, IR=0, DR=0 | (ME=1, IR=1, DR=1, RFID) | V machine_check_common ME=1, IR=1, DR=1 . . . Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-10-30 22:34:08 +08:00
std r11,GPR1(r1) /* Save r1 on the stack. */
std r11,0(r1) /* make stack chain pointer */
mfspr r11,SPRN_SRR0 /* Save SRR0 */
std r11,_NIP(r1)
mfspr r11,SPRN_SRR1 /* Save SRR1 */
std r11,_MSR(r1)
mfspr r11,SPRN_DAR /* Save DAR */
std r11,_DAR(r1)
mfspr r11,SPRN_DSISR /* Save DSISR */
std r11,_DSISR(r1)
std r9,_CCR(r1) /* Save CR in stackframe */
/* Save r9 through r13 from EXMC save area to stack frame. */
EXCEPTION_PROLOG_COMMON_2(PACA_EXMC)
mfmsr r11 /* get MSR value */
ori r11,r11,MSR_ME /* turn on ME bit */
ori r11,r11,MSR_RI /* turn on RI bit */
ld r12,PACAKBASE(r13) /* get high part of &label */
LOAD_HANDLER(r12, machine_check_handle_early)
1: mtspr SPRN_SRR0,r12
powerpc/book3s: handle machine check in Linux host. Move machine check entry point into Linux. So far we were dependent on firmware to decode MCE error details and handover the high level info to OS. This patch introduces early machine check routine that saves the MCE information (srr1, srr0, dar and dsisr) to the emergency stack. We allocate stack frame on emergency stack and set the r1 accordingly. This allows us to be prepared to take another exception without loosing context. One thing to note here that, if we get another machine check while ME bit is off then we risk a checkstop. Hence we restrict ourselves to save only MCE information and register saved on PACA_EXMC save are before we turn the ME bit on. We use paca->in_mce flag to differentiate between first entry and nested machine check entry which helps proper use of emergency stack. We increment paca->in_mce every time we enter in early machine check handler and decrement it while leaving. When we enter machine check early handler first time (paca->in_mce == 0), we are sure nobody is using MC emergency stack and allocate a stack frame at the start of the emergency stack. During subsequent entry (paca->in_mce > 0), we know that r1 points inside emergency stack and we allocate separate stack frame accordingly. This prevents us from clobbering MCE information during nested machine checks. The early machine check handler changes are placed under CPU_FTR_HVMODE section. This makes sure that the early machine check handler will get executed only in hypervisor kernel. This is the code flow: Machine Check Interrupt | V 0x200 vector ME=0, IR=0, DR=0 | V +-----------------------------------------------+ |machine_check_pSeries_early: | ME=0, IR=0, DR=0 | Alloc frame on emergency stack | | Save srr1, srr0, dar and dsisr on stack | +-----------------------------------------------+ | (ME=1, IR=0, DR=0, RFID) | V machine_check_handle_early ME=1, IR=0, DR=0 | V +-----------------------------------------------+ | machine_check_early (r3=pt_regs) | ME=1, IR=0, DR=0 | Things to do: (in next patches) | | Flush SLB for SLB errors | | Flush TLB for TLB errors | | Decode and save MCE info | +-----------------------------------------------+ | (Fall through existing exception handler routine.) | V machine_check_pSerie ME=1, IR=0, DR=0 | (ME=1, IR=1, DR=1, RFID) | V machine_check_common ME=1, IR=1, DR=1 . . . Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-10-30 22:34:08 +08:00
mtspr SPRN_SRR1,r11
rfid
b . /* prevent speculative execution */
2:
/* Stack overflow. Stay on emergency stack and panic.
* Keep the ME bit off while panic-ing, so that if we hit
* another machine check we checkstop.
*/
addi r1,r1,INT_FRAME_SIZE /* go back to previous stack frame */
ld r11,PACAKMSR(r13)
ld r12,PACAKBASE(r13)
LOAD_HANDLER(r12, unrecover_mce)
li r10,MSR_ME
andc r11,r11,r10 /* Turn off MSR_ME */
b 1b
b . /* prevent speculative execution */
powerpc/book3s: handle machine check in Linux host. Move machine check entry point into Linux. So far we were dependent on firmware to decode MCE error details and handover the high level info to OS. This patch introduces early machine check routine that saves the MCE information (srr1, srr0, dar and dsisr) to the emergency stack. We allocate stack frame on emergency stack and set the r1 accordingly. This allows us to be prepared to take another exception without loosing context. One thing to note here that, if we get another machine check while ME bit is off then we risk a checkstop. Hence we restrict ourselves to save only MCE information and register saved on PACA_EXMC save are before we turn the ME bit on. We use paca->in_mce flag to differentiate between first entry and nested machine check entry which helps proper use of emergency stack. We increment paca->in_mce every time we enter in early machine check handler and decrement it while leaving. When we enter machine check early handler first time (paca->in_mce == 0), we are sure nobody is using MC emergency stack and allocate a stack frame at the start of the emergency stack. During subsequent entry (paca->in_mce > 0), we know that r1 points inside emergency stack and we allocate separate stack frame accordingly. This prevents us from clobbering MCE information during nested machine checks. The early machine check handler changes are placed under CPU_FTR_HVMODE section. This makes sure that the early machine check handler will get executed only in hypervisor kernel. This is the code flow: Machine Check Interrupt | V 0x200 vector ME=0, IR=0, DR=0 | V +-----------------------------------------------+ |machine_check_pSeries_early: | ME=0, IR=0, DR=0 | Alloc frame on emergency stack | | Save srr1, srr0, dar and dsisr on stack | +-----------------------------------------------+ | (ME=1, IR=0, DR=0, RFID) | V machine_check_handle_early ME=1, IR=0, DR=0 | V +-----------------------------------------------+ | machine_check_early (r3=pt_regs) | ME=1, IR=0, DR=0 | Things to do: (in next patches) | | Flush SLB for SLB errors | | Flush TLB for TLB errors | | Decode and save MCE info | +-----------------------------------------------+ | (Fall through existing exception handler routine.) | V machine_check_pSerie ME=1, IR=0, DR=0 | (ME=1, IR=1, DR=1, RFID) | V machine_check_common ME=1, IR=1, DR=1 . . . Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-10-30 22:34:08 +08:00
END_FTR_SECTION_IFSET(CPU_FTR_HVMODE)
machine_check_pSeries:
.globl machine_check_fwnmi
machine_check_fwnmi:
HMT_MEDIUM_PPR_DISCARD
SET_SCRATCH0(r13) /* save r13 */
powerpc: Save CFAR before branching in interrupt entry paths Some of the interrupt vectors on 64-bit POWER server processors are only 32 bytes long, which is not enough for the full first-level interrupt handler. For these we currently just have a branch to an out-of-line handler. However, this means that we corrupt the CFAR (come-from address register) on POWER7 and later processors. To fix this, we split the EXCEPTION_PROLOG_1 macro into two pieces: EXCEPTION_PROLOG_0 contains the part up to the point where the CFAR is saved in the PACA, and EXCEPTION_PROLOG_1 contains the rest. We then put EXCEPTION_PROLOG_0 in the short interrupt vectors before we branch to the out-of-line handler, which contains the rest of the first-level interrupt handler. To facilitate this, we define new _OOL (out of line) variants of STD_EXCEPTION_PSERIES, etc. In order to get EXCEPTION_PROLOG_0 to be short enough, i.e., no more than 6 instructions, it was necessary to move the stores that move the PPR and CFAR values into the PACA into __EXCEPTION_PROLOG_1 and to get rid of one of the two HMT_MEDIUM instructions. Previously there was a HMT_MEDIUM_PPR_DISCARD before the prolog, which was nop'd out on processors with the PPR (POWER7 and later), and then another HMT_MEDIUM inside the HMT_MEDIUM_PPR_SAVE macro call inside __EXCEPTION_PROLOG_1, which was nop'd out on processors without PPR. Now the HMT_MEDIUM inside EXCEPTION_PROLOG_0 is there unconditionally and the HMT_MEDIUM_PPR_DISCARD is not strictly necessary, although this leaves it in for the interrupt vectors where there is room for it. Previously we had a handler for hypervisor maintenance interrupts at 0xe50, which doesn't leave enough room for the vector for hypervisor emulation assist interrupts at 0xe40, since we need 8 instructions. The 0xe50 vector was only used on POWER6, as the HMI vector was moved to 0xe60 on POWER7. Since we don't support running in hypervisor mode on POWER6, we just remove the handler at 0xe50. This also changes denorm_exception_hv to use EXCEPTION_PROLOG_0 instead of open-coding it, and removes the HMT_MEDIUM_PPR_DISCARD from the relocation-on vectors (since any CPU that supports relocation-on interrupts also has the PPR). Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-02-05 02:10:15 +08:00
EXCEPTION_PROLOG_0(PACA_EXMC)
machine_check_pSeries_0:
EXCEPTION_PROLOG_1(PACA_EXMC, KVMTEST, 0x200)
EXCEPTION_PROLOG_PSERIES_1(machine_check_common, EXC_STD)
KVM_HANDLER_SKIP(PACA_EXMC, EXC_STD, 0x200)
KVM_HANDLER_SKIP(PACA_EXGEN, EXC_STD, 0x300)
KVM_HANDLER_SKIP(PACA_EXSLB, EXC_STD, 0x380)
KVM: PPC: Add support for Book3S processors in hypervisor mode This adds support for KVM running on 64-bit Book 3S processors, specifically POWER7, in hypervisor mode. Using hypervisor mode means that the guest can use the processor's supervisor mode. That means that the guest can execute privileged instructions and access privileged registers itself without trapping to the host. This gives excellent performance, but does mean that KVM cannot emulate a processor architecture other than the one that the hardware implements. This code assumes that the guest is running paravirtualized using the PAPR (Power Architecture Platform Requirements) interface, which is the interface that IBM's PowerVM hypervisor uses. That means that existing Linux distributions that run on IBM pSeries machines will also run under KVM without modification. In order to communicate the PAPR hypercalls to qemu, this adds a new KVM_EXIT_PAPR_HCALL exit code to include/linux/kvm.h. Currently the choice between book3s_hv support and book3s_pr support (i.e. the existing code, which runs the guest in user mode) has to be made at kernel configuration time, so a given kernel binary can only do one or the other. This new book3s_hv code doesn't support MMIO emulation at present. Since we are running paravirtualized guests, this isn't a serious restriction. With the guest running in supervisor mode, most exceptions go straight to the guest. We will never get data or instruction storage or segment interrupts, alignment interrupts, decrementer interrupts, program interrupts, single-step interrupts, etc., coming to the hypervisor from the guest. Therefore this introduces a new KVMTEST_NONHV macro for the exception entry path so that we don't have to do the KVM test on entry to those exception handlers. We do however get hypervisor decrementer, hypervisor data storage, hypervisor instruction storage, and hypervisor emulation assist interrupts, so we have to handle those. In hypervisor mode, real-mode accesses can access all of RAM, not just a limited amount. Therefore we put all the guest state in the vcpu.arch and use the shadow_vcpu in the PACA only for temporary scratch space. We allocate the vcpu with kzalloc rather than vzalloc, and we don't use anything in the kvmppc_vcpu_book3s struct, so we don't allocate it. We don't have a shared page with the guest, but we still need a kvm_vcpu_arch_shared struct to store the values of various registers, so we include one in the vcpu_arch struct. The POWER7 processor has a restriction that all threads in a core have to be in the same partition. MMU-on kernel code counts as a partition (partition 0), so we have to do a partition switch on every entry to and exit from the guest. At present we require the host and guest to run in single-thread mode because of this hardware restriction. This code allocates a hashed page table for the guest and initializes it with HPTEs for the guest's Virtual Real Memory Area (VRMA). We require that the guest memory is allocated using 16MB huge pages, in order to simplify the low-level memory management. This also means that we can get away without tracking paging activity in the host for now, since huge pages can't be paged or swapped. This also adds a few new exports needed by the book3s_hv code. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2011-06-29 08:21:34 +08:00
KVM_HANDLER_PR(PACA_EXGEN, EXC_STD, 0x400)
KVM_HANDLER_PR(PACA_EXSLB, EXC_STD, 0x480)
KVM_HANDLER_PR(PACA_EXGEN, EXC_STD, 0x900)
KVM_HANDLER(PACA_EXGEN, EXC_HV, 0x982)
#ifdef CONFIG_PPC_DENORMALISATION
denorm_assist:
BEGIN_FTR_SECTION
/*
* To denormalise we need to move a copy of the register to itself.
* For POWER6 do that here for all FP regs.
*/
mfmsr r10
ori r10,r10,(MSR_FP|MSR_FE0|MSR_FE1)
xori r10,r10,(MSR_FE0|MSR_FE1)
mtmsrd r10
sync
#define FMR2(n) fmr (n), (n) ; fmr n+1, n+1
#define FMR4(n) FMR2(n) ; FMR2(n+2)
#define FMR8(n) FMR4(n) ; FMR4(n+4)
#define FMR16(n) FMR8(n) ; FMR8(n+8)
#define FMR32(n) FMR16(n) ; FMR16(n+16)
FMR32(0)
FTR_SECTION_ELSE
/*
* To denormalise we need to move a copy of the register to itself.
* For POWER7 do that here for the first 32 VSX registers only.
*/
mfmsr r10
oris r10,r10,MSR_VSX@h
mtmsrd r10
sync
#define XVCPSGNDP2(n) XVCPSGNDP(n,n,n) ; XVCPSGNDP(n+1,n+1,n+1)
#define XVCPSGNDP4(n) XVCPSGNDP2(n) ; XVCPSGNDP2(n+2)
#define XVCPSGNDP8(n) XVCPSGNDP4(n) ; XVCPSGNDP4(n+4)
#define XVCPSGNDP16(n) XVCPSGNDP8(n) ; XVCPSGNDP8(n+8)
#define XVCPSGNDP32(n) XVCPSGNDP16(n) ; XVCPSGNDP16(n+16)
XVCPSGNDP32(0)
ALT_FTR_SECTION_END_IFCLR(CPU_FTR_ARCH_206)
BEGIN_FTR_SECTION
b denorm_done
END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_207S)
/*
* To denormalise we need to move a copy of the register to itself.
* For POWER8 we need to do that for all 64 VSX registers
*/
XVCPSGNDP32(32)
denorm_done:
mtspr SPRN_HSRR0,r11
mtcrf 0x80,r9
ld r9,PACA_EXGEN+EX_R9(r13)
RESTORE_PPR_PACA(PACA_EXGEN, r10)
BEGIN_FTR_SECTION
ld r10,PACA_EXGEN+EX_CFAR(r13)
mtspr SPRN_CFAR,r10
END_FTR_SECTION_IFSET(CPU_FTR_CFAR)
ld r10,PACA_EXGEN+EX_R10(r13)
ld r11,PACA_EXGEN+EX_R11(r13)
ld r12,PACA_EXGEN+EX_R12(r13)
ld r13,PACA_EXGEN+EX_R13(r13)
HRFID
b .
#endif
.align 7
/* moved from 0xe00 */
powerpc: Save CFAR before branching in interrupt entry paths Some of the interrupt vectors on 64-bit POWER server processors are only 32 bytes long, which is not enough for the full first-level interrupt handler. For these we currently just have a branch to an out-of-line handler. However, this means that we corrupt the CFAR (come-from address register) on POWER7 and later processors. To fix this, we split the EXCEPTION_PROLOG_1 macro into two pieces: EXCEPTION_PROLOG_0 contains the part up to the point where the CFAR is saved in the PACA, and EXCEPTION_PROLOG_1 contains the rest. We then put EXCEPTION_PROLOG_0 in the short interrupt vectors before we branch to the out-of-line handler, which contains the rest of the first-level interrupt handler. To facilitate this, we define new _OOL (out of line) variants of STD_EXCEPTION_PSERIES, etc. In order to get EXCEPTION_PROLOG_0 to be short enough, i.e., no more than 6 instructions, it was necessary to move the stores that move the PPR and CFAR values into the PACA into __EXCEPTION_PROLOG_1 and to get rid of one of the two HMT_MEDIUM instructions. Previously there was a HMT_MEDIUM_PPR_DISCARD before the prolog, which was nop'd out on processors with the PPR (POWER7 and later), and then another HMT_MEDIUM inside the HMT_MEDIUM_PPR_SAVE macro call inside __EXCEPTION_PROLOG_1, which was nop'd out on processors without PPR. Now the HMT_MEDIUM inside EXCEPTION_PROLOG_0 is there unconditionally and the HMT_MEDIUM_PPR_DISCARD is not strictly necessary, although this leaves it in for the interrupt vectors where there is room for it. Previously we had a handler for hypervisor maintenance interrupts at 0xe50, which doesn't leave enough room for the vector for hypervisor emulation assist interrupts at 0xe40, since we need 8 instructions. The 0xe50 vector was only used on POWER6, as the HMI vector was moved to 0xe60 on POWER7. Since we don't support running in hypervisor mode on POWER6, we just remove the handler at 0xe50. This also changes denorm_exception_hv to use EXCEPTION_PROLOG_0 instead of open-coding it, and removes the HMT_MEDIUM_PPR_DISCARD from the relocation-on vectors (since any CPU that supports relocation-on interrupts also has the PPR). Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-02-05 02:10:15 +08:00
STD_EXCEPTION_HV_OOL(0xe02, h_data_storage)
KVM_HANDLER_SKIP(PACA_EXGEN, EXC_HV, 0xe02)
powerpc: Save CFAR before branching in interrupt entry paths Some of the interrupt vectors on 64-bit POWER server processors are only 32 bytes long, which is not enough for the full first-level interrupt handler. For these we currently just have a branch to an out-of-line handler. However, this means that we corrupt the CFAR (come-from address register) on POWER7 and later processors. To fix this, we split the EXCEPTION_PROLOG_1 macro into two pieces: EXCEPTION_PROLOG_0 contains the part up to the point where the CFAR is saved in the PACA, and EXCEPTION_PROLOG_1 contains the rest. We then put EXCEPTION_PROLOG_0 in the short interrupt vectors before we branch to the out-of-line handler, which contains the rest of the first-level interrupt handler. To facilitate this, we define new _OOL (out of line) variants of STD_EXCEPTION_PSERIES, etc. In order to get EXCEPTION_PROLOG_0 to be short enough, i.e., no more than 6 instructions, it was necessary to move the stores that move the PPR and CFAR values into the PACA into __EXCEPTION_PROLOG_1 and to get rid of one of the two HMT_MEDIUM instructions. Previously there was a HMT_MEDIUM_PPR_DISCARD before the prolog, which was nop'd out on processors with the PPR (POWER7 and later), and then another HMT_MEDIUM inside the HMT_MEDIUM_PPR_SAVE macro call inside __EXCEPTION_PROLOG_1, which was nop'd out on processors without PPR. Now the HMT_MEDIUM inside EXCEPTION_PROLOG_0 is there unconditionally and the HMT_MEDIUM_PPR_DISCARD is not strictly necessary, although this leaves it in for the interrupt vectors where there is room for it. Previously we had a handler for hypervisor maintenance interrupts at 0xe50, which doesn't leave enough room for the vector for hypervisor emulation assist interrupts at 0xe40, since we need 8 instructions. The 0xe50 vector was only used on POWER6, as the HMI vector was moved to 0xe60 on POWER7. Since we don't support running in hypervisor mode on POWER6, we just remove the handler at 0xe50. This also changes denorm_exception_hv to use EXCEPTION_PROLOG_0 instead of open-coding it, and removes the HMT_MEDIUM_PPR_DISCARD from the relocation-on vectors (since any CPU that supports relocation-on interrupts also has the PPR). Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-02-05 02:10:15 +08:00
STD_EXCEPTION_HV_OOL(0xe22, h_instr_storage)
KVM_HANDLER(PACA_EXGEN, EXC_HV, 0xe22)
powerpc: Save CFAR before branching in interrupt entry paths Some of the interrupt vectors on 64-bit POWER server processors are only 32 bytes long, which is not enough for the full first-level interrupt handler. For these we currently just have a branch to an out-of-line handler. However, this means that we corrupt the CFAR (come-from address register) on POWER7 and later processors. To fix this, we split the EXCEPTION_PROLOG_1 macro into two pieces: EXCEPTION_PROLOG_0 contains the part up to the point where the CFAR is saved in the PACA, and EXCEPTION_PROLOG_1 contains the rest. We then put EXCEPTION_PROLOG_0 in the short interrupt vectors before we branch to the out-of-line handler, which contains the rest of the first-level interrupt handler. To facilitate this, we define new _OOL (out of line) variants of STD_EXCEPTION_PSERIES, etc. In order to get EXCEPTION_PROLOG_0 to be short enough, i.e., no more than 6 instructions, it was necessary to move the stores that move the PPR and CFAR values into the PACA into __EXCEPTION_PROLOG_1 and to get rid of one of the two HMT_MEDIUM instructions. Previously there was a HMT_MEDIUM_PPR_DISCARD before the prolog, which was nop'd out on processors with the PPR (POWER7 and later), and then another HMT_MEDIUM inside the HMT_MEDIUM_PPR_SAVE macro call inside __EXCEPTION_PROLOG_1, which was nop'd out on processors without PPR. Now the HMT_MEDIUM inside EXCEPTION_PROLOG_0 is there unconditionally and the HMT_MEDIUM_PPR_DISCARD is not strictly necessary, although this leaves it in for the interrupt vectors where there is room for it. Previously we had a handler for hypervisor maintenance interrupts at 0xe50, which doesn't leave enough room for the vector for hypervisor emulation assist interrupts at 0xe40, since we need 8 instructions. The 0xe50 vector was only used on POWER6, as the HMI vector was moved to 0xe60 on POWER7. Since we don't support running in hypervisor mode on POWER6, we just remove the handler at 0xe50. This also changes denorm_exception_hv to use EXCEPTION_PROLOG_0 instead of open-coding it, and removes the HMT_MEDIUM_PPR_DISCARD from the relocation-on vectors (since any CPU that supports relocation-on interrupts also has the PPR). Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-02-05 02:10:15 +08:00
STD_EXCEPTION_HV_OOL(0xe42, emulation_assist)
KVM_HANDLER(PACA_EXGEN, EXC_HV, 0xe42)
MASKABLE_EXCEPTION_HV_OOL(0xe62, hmi_exception)
KVM_HANDLER(PACA_EXGEN, EXC_HV, 0xe62)
powerpc: Save CFAR before branching in interrupt entry paths Some of the interrupt vectors on 64-bit POWER server processors are only 32 bytes long, which is not enough for the full first-level interrupt handler. For these we currently just have a branch to an out-of-line handler. However, this means that we corrupt the CFAR (come-from address register) on POWER7 and later processors. To fix this, we split the EXCEPTION_PROLOG_1 macro into two pieces: EXCEPTION_PROLOG_0 contains the part up to the point where the CFAR is saved in the PACA, and EXCEPTION_PROLOG_1 contains the rest. We then put EXCEPTION_PROLOG_0 in the short interrupt vectors before we branch to the out-of-line handler, which contains the rest of the first-level interrupt handler. To facilitate this, we define new _OOL (out of line) variants of STD_EXCEPTION_PSERIES, etc. In order to get EXCEPTION_PROLOG_0 to be short enough, i.e., no more than 6 instructions, it was necessary to move the stores that move the PPR and CFAR values into the PACA into __EXCEPTION_PROLOG_1 and to get rid of one of the two HMT_MEDIUM instructions. Previously there was a HMT_MEDIUM_PPR_DISCARD before the prolog, which was nop'd out on processors with the PPR (POWER7 and later), and then another HMT_MEDIUM inside the HMT_MEDIUM_PPR_SAVE macro call inside __EXCEPTION_PROLOG_1, which was nop'd out on processors without PPR. Now the HMT_MEDIUM inside EXCEPTION_PROLOG_0 is there unconditionally and the HMT_MEDIUM_PPR_DISCARD is not strictly necessary, although this leaves it in for the interrupt vectors where there is room for it. Previously we had a handler for hypervisor maintenance interrupts at 0xe50, which doesn't leave enough room for the vector for hypervisor emulation assist interrupts at 0xe40, since we need 8 instructions. The 0xe50 vector was only used on POWER6, as the HMI vector was moved to 0xe60 on POWER7. Since we don't support running in hypervisor mode on POWER6, we just remove the handler at 0xe50. This also changes denorm_exception_hv to use EXCEPTION_PROLOG_0 instead of open-coding it, and removes the HMT_MEDIUM_PPR_DISCARD from the relocation-on vectors (since any CPU that supports relocation-on interrupts also has the PPR). Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-02-05 02:10:15 +08:00
MASKABLE_EXCEPTION_HV_OOL(0xe82, h_doorbell)
KVM_HANDLER(PACA_EXGEN, EXC_HV, 0xe82)
/* moved from 0xf00 */
powerpc: Save CFAR before branching in interrupt entry paths Some of the interrupt vectors on 64-bit POWER server processors are only 32 bytes long, which is not enough for the full first-level interrupt handler. For these we currently just have a branch to an out-of-line handler. However, this means that we corrupt the CFAR (come-from address register) on POWER7 and later processors. To fix this, we split the EXCEPTION_PROLOG_1 macro into two pieces: EXCEPTION_PROLOG_0 contains the part up to the point where the CFAR is saved in the PACA, and EXCEPTION_PROLOG_1 contains the rest. We then put EXCEPTION_PROLOG_0 in the short interrupt vectors before we branch to the out-of-line handler, which contains the rest of the first-level interrupt handler. To facilitate this, we define new _OOL (out of line) variants of STD_EXCEPTION_PSERIES, etc. In order to get EXCEPTION_PROLOG_0 to be short enough, i.e., no more than 6 instructions, it was necessary to move the stores that move the PPR and CFAR values into the PACA into __EXCEPTION_PROLOG_1 and to get rid of one of the two HMT_MEDIUM instructions. Previously there was a HMT_MEDIUM_PPR_DISCARD before the prolog, which was nop'd out on processors with the PPR (POWER7 and later), and then another HMT_MEDIUM inside the HMT_MEDIUM_PPR_SAVE macro call inside __EXCEPTION_PROLOG_1, which was nop'd out on processors without PPR. Now the HMT_MEDIUM inside EXCEPTION_PROLOG_0 is there unconditionally and the HMT_MEDIUM_PPR_DISCARD is not strictly necessary, although this leaves it in for the interrupt vectors where there is room for it. Previously we had a handler for hypervisor maintenance interrupts at 0xe50, which doesn't leave enough room for the vector for hypervisor emulation assist interrupts at 0xe40, since we need 8 instructions. The 0xe50 vector was only used on POWER6, as the HMI vector was moved to 0xe60 on POWER7. Since we don't support running in hypervisor mode on POWER6, we just remove the handler at 0xe50. This also changes denorm_exception_hv to use EXCEPTION_PROLOG_0 instead of open-coding it, and removes the HMT_MEDIUM_PPR_DISCARD from the relocation-on vectors (since any CPU that supports relocation-on interrupts also has the PPR). Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-02-05 02:10:15 +08:00
STD_EXCEPTION_PSERIES_OOL(0xf00, performance_monitor)
KVM: PPC: Add support for Book3S processors in hypervisor mode This adds support for KVM running on 64-bit Book 3S processors, specifically POWER7, in hypervisor mode. Using hypervisor mode means that the guest can use the processor's supervisor mode. That means that the guest can execute privileged instructions and access privileged registers itself without trapping to the host. This gives excellent performance, but does mean that KVM cannot emulate a processor architecture other than the one that the hardware implements. This code assumes that the guest is running paravirtualized using the PAPR (Power Architecture Platform Requirements) interface, which is the interface that IBM's PowerVM hypervisor uses. That means that existing Linux distributions that run on IBM pSeries machines will also run under KVM without modification. In order to communicate the PAPR hypercalls to qemu, this adds a new KVM_EXIT_PAPR_HCALL exit code to include/linux/kvm.h. Currently the choice between book3s_hv support and book3s_pr support (i.e. the existing code, which runs the guest in user mode) has to be made at kernel configuration time, so a given kernel binary can only do one or the other. This new book3s_hv code doesn't support MMIO emulation at present. Since we are running paravirtualized guests, this isn't a serious restriction. With the guest running in supervisor mode, most exceptions go straight to the guest. We will never get data or instruction storage or segment interrupts, alignment interrupts, decrementer interrupts, program interrupts, single-step interrupts, etc., coming to the hypervisor from the guest. Therefore this introduces a new KVMTEST_NONHV macro for the exception entry path so that we don't have to do the KVM test on entry to those exception handlers. We do however get hypervisor decrementer, hypervisor data storage, hypervisor instruction storage, and hypervisor emulation assist interrupts, so we have to handle those. In hypervisor mode, real-mode accesses can access all of RAM, not just a limited amount. Therefore we put all the guest state in the vcpu.arch and use the shadow_vcpu in the PACA only for temporary scratch space. We allocate the vcpu with kzalloc rather than vzalloc, and we don't use anything in the kvmppc_vcpu_book3s struct, so we don't allocate it. We don't have a shared page with the guest, but we still need a kvm_vcpu_arch_shared struct to store the values of various registers, so we include one in the vcpu_arch struct. The POWER7 processor has a restriction that all threads in a core have to be in the same partition. MMU-on kernel code counts as a partition (partition 0), so we have to do a partition switch on every entry to and exit from the guest. At present we require the host and guest to run in single-thread mode because of this hardware restriction. This code allocates a hashed page table for the guest and initializes it with HPTEs for the guest's Virtual Real Memory Area (VRMA). We require that the guest memory is allocated using 16MB huge pages, in order to simplify the low-level memory management. This also means that we can get away without tracking paging activity in the host for now, since huge pages can't be paged or swapped. This also adds a few new exports needed by the book3s_hv code. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2011-06-29 08:21:34 +08:00
KVM_HANDLER_PR(PACA_EXGEN, EXC_STD, 0xf00)
powerpc: Save CFAR before branching in interrupt entry paths Some of the interrupt vectors on 64-bit POWER server processors are only 32 bytes long, which is not enough for the full first-level interrupt handler. For these we currently just have a branch to an out-of-line handler. However, this means that we corrupt the CFAR (come-from address register) on POWER7 and later processors. To fix this, we split the EXCEPTION_PROLOG_1 macro into two pieces: EXCEPTION_PROLOG_0 contains the part up to the point where the CFAR is saved in the PACA, and EXCEPTION_PROLOG_1 contains the rest. We then put EXCEPTION_PROLOG_0 in the short interrupt vectors before we branch to the out-of-line handler, which contains the rest of the first-level interrupt handler. To facilitate this, we define new _OOL (out of line) variants of STD_EXCEPTION_PSERIES, etc. In order to get EXCEPTION_PROLOG_0 to be short enough, i.e., no more than 6 instructions, it was necessary to move the stores that move the PPR and CFAR values into the PACA into __EXCEPTION_PROLOG_1 and to get rid of one of the two HMT_MEDIUM instructions. Previously there was a HMT_MEDIUM_PPR_DISCARD before the prolog, which was nop'd out on processors with the PPR (POWER7 and later), and then another HMT_MEDIUM inside the HMT_MEDIUM_PPR_SAVE macro call inside __EXCEPTION_PROLOG_1, which was nop'd out on processors without PPR. Now the HMT_MEDIUM inside EXCEPTION_PROLOG_0 is there unconditionally and the HMT_MEDIUM_PPR_DISCARD is not strictly necessary, although this leaves it in for the interrupt vectors where there is room for it. Previously we had a handler for hypervisor maintenance interrupts at 0xe50, which doesn't leave enough room for the vector for hypervisor emulation assist interrupts at 0xe40, since we need 8 instructions. The 0xe50 vector was only used on POWER6, as the HMI vector was moved to 0xe60 on POWER7. Since we don't support running in hypervisor mode on POWER6, we just remove the handler at 0xe50. This also changes denorm_exception_hv to use EXCEPTION_PROLOG_0 instead of open-coding it, and removes the HMT_MEDIUM_PPR_DISCARD from the relocation-on vectors (since any CPU that supports relocation-on interrupts also has the PPR). Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-02-05 02:10:15 +08:00
STD_EXCEPTION_PSERIES_OOL(0xf20, altivec_unavailable)
KVM: PPC: Add support for Book3S processors in hypervisor mode This adds support for KVM running on 64-bit Book 3S processors, specifically POWER7, in hypervisor mode. Using hypervisor mode means that the guest can use the processor's supervisor mode. That means that the guest can execute privileged instructions and access privileged registers itself without trapping to the host. This gives excellent performance, but does mean that KVM cannot emulate a processor architecture other than the one that the hardware implements. This code assumes that the guest is running paravirtualized using the PAPR (Power Architecture Platform Requirements) interface, which is the interface that IBM's PowerVM hypervisor uses. That means that existing Linux distributions that run on IBM pSeries machines will also run under KVM without modification. In order to communicate the PAPR hypercalls to qemu, this adds a new KVM_EXIT_PAPR_HCALL exit code to include/linux/kvm.h. Currently the choice between book3s_hv support and book3s_pr support (i.e. the existing code, which runs the guest in user mode) has to be made at kernel configuration time, so a given kernel binary can only do one or the other. This new book3s_hv code doesn't support MMIO emulation at present. Since we are running paravirtualized guests, this isn't a serious restriction. With the guest running in supervisor mode, most exceptions go straight to the guest. We will never get data or instruction storage or segment interrupts, alignment interrupts, decrementer interrupts, program interrupts, single-step interrupts, etc., coming to the hypervisor from the guest. Therefore this introduces a new KVMTEST_NONHV macro for the exception entry path so that we don't have to do the KVM test on entry to those exception handlers. We do however get hypervisor decrementer, hypervisor data storage, hypervisor instruction storage, and hypervisor emulation assist interrupts, so we have to handle those. In hypervisor mode, real-mode accesses can access all of RAM, not just a limited amount. Therefore we put all the guest state in the vcpu.arch and use the shadow_vcpu in the PACA only for temporary scratch space. We allocate the vcpu with kzalloc rather than vzalloc, and we don't use anything in the kvmppc_vcpu_book3s struct, so we don't allocate it. We don't have a shared page with the guest, but we still need a kvm_vcpu_arch_shared struct to store the values of various registers, so we include one in the vcpu_arch struct. The POWER7 processor has a restriction that all threads in a core have to be in the same partition. MMU-on kernel code counts as a partition (partition 0), so we have to do a partition switch on every entry to and exit from the guest. At present we require the host and guest to run in single-thread mode because of this hardware restriction. This code allocates a hashed page table for the guest and initializes it with HPTEs for the guest's Virtual Real Memory Area (VRMA). We require that the guest memory is allocated using 16MB huge pages, in order to simplify the low-level memory management. This also means that we can get away without tracking paging activity in the host for now, since huge pages can't be paged or swapped. This also adds a few new exports needed by the book3s_hv code. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2011-06-29 08:21:34 +08:00
KVM_HANDLER_PR(PACA_EXGEN, EXC_STD, 0xf20)
powerpc: Save CFAR before branching in interrupt entry paths Some of the interrupt vectors on 64-bit POWER server processors are only 32 bytes long, which is not enough for the full first-level interrupt handler. For these we currently just have a branch to an out-of-line handler. However, this means that we corrupt the CFAR (come-from address register) on POWER7 and later processors. To fix this, we split the EXCEPTION_PROLOG_1 macro into two pieces: EXCEPTION_PROLOG_0 contains the part up to the point where the CFAR is saved in the PACA, and EXCEPTION_PROLOG_1 contains the rest. We then put EXCEPTION_PROLOG_0 in the short interrupt vectors before we branch to the out-of-line handler, which contains the rest of the first-level interrupt handler. To facilitate this, we define new _OOL (out of line) variants of STD_EXCEPTION_PSERIES, etc. In order to get EXCEPTION_PROLOG_0 to be short enough, i.e., no more than 6 instructions, it was necessary to move the stores that move the PPR and CFAR values into the PACA into __EXCEPTION_PROLOG_1 and to get rid of one of the two HMT_MEDIUM instructions. Previously there was a HMT_MEDIUM_PPR_DISCARD before the prolog, which was nop'd out on processors with the PPR (POWER7 and later), and then another HMT_MEDIUM inside the HMT_MEDIUM_PPR_SAVE macro call inside __EXCEPTION_PROLOG_1, which was nop'd out on processors without PPR. Now the HMT_MEDIUM inside EXCEPTION_PROLOG_0 is there unconditionally and the HMT_MEDIUM_PPR_DISCARD is not strictly necessary, although this leaves it in for the interrupt vectors where there is room for it. Previously we had a handler for hypervisor maintenance interrupts at 0xe50, which doesn't leave enough room for the vector for hypervisor emulation assist interrupts at 0xe40, since we need 8 instructions. The 0xe50 vector was only used on POWER6, as the HMI vector was moved to 0xe60 on POWER7. Since we don't support running in hypervisor mode on POWER6, we just remove the handler at 0xe50. This also changes denorm_exception_hv to use EXCEPTION_PROLOG_0 instead of open-coding it, and removes the HMT_MEDIUM_PPR_DISCARD from the relocation-on vectors (since any CPU that supports relocation-on interrupts also has the PPR). Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-02-05 02:10:15 +08:00
STD_EXCEPTION_PSERIES_OOL(0xf40, vsx_unavailable)
KVM: PPC: Add support for Book3S processors in hypervisor mode This adds support for KVM running on 64-bit Book 3S processors, specifically POWER7, in hypervisor mode. Using hypervisor mode means that the guest can use the processor's supervisor mode. That means that the guest can execute privileged instructions and access privileged registers itself without trapping to the host. This gives excellent performance, but does mean that KVM cannot emulate a processor architecture other than the one that the hardware implements. This code assumes that the guest is running paravirtualized using the PAPR (Power Architecture Platform Requirements) interface, which is the interface that IBM's PowerVM hypervisor uses. That means that existing Linux distributions that run on IBM pSeries machines will also run under KVM without modification. In order to communicate the PAPR hypercalls to qemu, this adds a new KVM_EXIT_PAPR_HCALL exit code to include/linux/kvm.h. Currently the choice between book3s_hv support and book3s_pr support (i.e. the existing code, which runs the guest in user mode) has to be made at kernel configuration time, so a given kernel binary can only do one or the other. This new book3s_hv code doesn't support MMIO emulation at present. Since we are running paravirtualized guests, this isn't a serious restriction. With the guest running in supervisor mode, most exceptions go straight to the guest. We will never get data or instruction storage or segment interrupts, alignment interrupts, decrementer interrupts, program interrupts, single-step interrupts, etc., coming to the hypervisor from the guest. Therefore this introduces a new KVMTEST_NONHV macro for the exception entry path so that we don't have to do the KVM test on entry to those exception handlers. We do however get hypervisor decrementer, hypervisor data storage, hypervisor instruction storage, and hypervisor emulation assist interrupts, so we have to handle those. In hypervisor mode, real-mode accesses can access all of RAM, not just a limited amount. Therefore we put all the guest state in the vcpu.arch and use the shadow_vcpu in the PACA only for temporary scratch space. We allocate the vcpu with kzalloc rather than vzalloc, and we don't use anything in the kvmppc_vcpu_book3s struct, so we don't allocate it. We don't have a shared page with the guest, but we still need a kvm_vcpu_arch_shared struct to store the values of various registers, so we include one in the vcpu_arch struct. The POWER7 processor has a restriction that all threads in a core have to be in the same partition. MMU-on kernel code counts as a partition (partition 0), so we have to do a partition switch on every entry to and exit from the guest. At present we require the host and guest to run in single-thread mode because of this hardware restriction. This code allocates a hashed page table for the guest and initializes it with HPTEs for the guest's Virtual Real Memory Area (VRMA). We require that the guest memory is allocated using 16MB huge pages, in order to simplify the low-level memory management. This also means that we can get away without tracking paging activity in the host for now, since huge pages can't be paged or swapped. This also adds a few new exports needed by the book3s_hv code. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2011-06-29 08:21:34 +08:00
KVM_HANDLER_PR(PACA_EXGEN, EXC_STD, 0xf40)
STD_EXCEPTION_PSERIES_OOL(0xf60, facility_unavailable)
KVM_HANDLER_PR(PACA_EXGEN, EXC_STD, 0xf60)
STD_EXCEPTION_HV_OOL(0xf82, facility_unavailable)
KVM_HANDLER(PACA_EXGEN, EXC_HV, 0xf82)
/*
* An interrupt came in while soft-disabled. We set paca->irq_happened, then:
* - If it was a decrementer interrupt, we bump the dec to max and and return.
* - If it was a doorbell we return immediately since doorbells are edge
* triggered and won't automatically refire.
* - If it was a HMI we return immediately since we handled it in realmode
* and it won't refire.
* - else we hard disable and return.
* This is called with r10 containing the value to OR to the paca field.
*/
powerpc: Rework lazy-interrupt handling The current implementation of lazy interrupts handling has some issues that this tries to address. We don't do the various workarounds we need to do when re-enabling interrupts in some cases such as when returning from an interrupt and thus we may still lose or get delayed decrementer or doorbell interrupts. The current scheme also makes it much harder to handle the external "edge" interrupts provided by some BookE processors when using the EPR facility (External Proxy) and the Freescale Hypervisor. Additionally, we tend to keep interrupts hard disabled in a number of cases, such as decrementer interrupts, external interrupts, or when a masked decrementer interrupt is pending. This is sub-optimal. This is an attempt at fixing it all in one go by reworking the way we do the lazy interrupt disabling from the ground up. The base idea is to replace the "hard_enabled" field with a "irq_happened" field in which we store a bit mask of what interrupt occurred while soft-disabled. When re-enabling, either via arch_local_irq_restore() or when returning from an interrupt, we can now decide what to do by testing bits in that field. We then implement replaying of the missed interrupts either by re-using the existing exception frame (in exception exit case) or via the creation of a new one from an assembly trampoline (in the arch_local_irq_enable case). This removes the need to play with the decrementer to try to create fake interrupts, among others. In addition, this adds a few refinements: - We no longer hard disable decrementer interrupts that occur while soft-disabled. We now simply bump the decrementer back to max (on BookS) or leave it stopped (on BookE) and continue with hard interrupts enabled, which means that we'll potentially get better sample quality from performance monitor interrupts. - Timer, decrementer and doorbell interrupts now hard-enable shortly after removing the source of the interrupt, which means they no longer run entirely hard disabled. Again, this will improve perf sample quality. - On Book3E 64-bit, we now make the performance monitor interrupt act as an NMI like Book3S (the necessary C code for that to work appear to already be present in the FSL perf code, notably calling nmi_enter instead of irq_enter). (This also fixes a bug where BookE perfmon interrupts could clobber r14 ... oops) - We could make "masked" decrementer interrupts act as NMIs when doing timer-based perf sampling to improve the sample quality. Signed-off-by-yet: Benjamin Herrenschmidt <benh@kernel.crashing.org> --- v2: - Add hard-enable to decrementer, timer and doorbells - Fix CR clobber in masked irq handling on BookE - Make embedded perf interrupt act as an NMI - Add a PACA_HAPPENED_EE_EDGE for use by FSL if they want to retrigger an interrupt without preventing hard-enable v3: - Fix or vs. ori bug on Book3E - Fix enabling of interrupts for some exceptions on Book3E v4: - Fix resend of doorbells on return from interrupt on Book3E v5: - Rebased on top of my latest series, which involves some significant rework of some aspects of the patch. v6: - 32-bit compile fix - more compile fixes with various .config combos - factor out the asm code to soft-disable interrupts - remove the C wrapper around preempt_schedule_irq v7: - Fix a bug with hard irq state tracking on native power7
2012-03-06 15:27:59 +08:00
#define MASKED_INTERRUPT(_H) \
masked_##_H##interrupt: \
std r11,PACA_EXGEN+EX_R11(r13); \
lbz r11,PACAIRQHAPPENED(r13); \
or r11,r11,r10; \
stb r11,PACAIRQHAPPENED(r13); \
cmpwi r10,PACA_IRQ_DEC; \
bne 1f; \
powerpc: Rework lazy-interrupt handling The current implementation of lazy interrupts handling has some issues that this tries to address. We don't do the various workarounds we need to do when re-enabling interrupts in some cases such as when returning from an interrupt and thus we may still lose or get delayed decrementer or doorbell interrupts. The current scheme also makes it much harder to handle the external "edge" interrupts provided by some BookE processors when using the EPR facility (External Proxy) and the Freescale Hypervisor. Additionally, we tend to keep interrupts hard disabled in a number of cases, such as decrementer interrupts, external interrupts, or when a masked decrementer interrupt is pending. This is sub-optimal. This is an attempt at fixing it all in one go by reworking the way we do the lazy interrupt disabling from the ground up. The base idea is to replace the "hard_enabled" field with a "irq_happened" field in which we store a bit mask of what interrupt occurred while soft-disabled. When re-enabling, either via arch_local_irq_restore() or when returning from an interrupt, we can now decide what to do by testing bits in that field. We then implement replaying of the missed interrupts either by re-using the existing exception frame (in exception exit case) or via the creation of a new one from an assembly trampoline (in the arch_local_irq_enable case). This removes the need to play with the decrementer to try to create fake interrupts, among others. In addition, this adds a few refinements: - We no longer hard disable decrementer interrupts that occur while soft-disabled. We now simply bump the decrementer back to max (on BookS) or leave it stopped (on BookE) and continue with hard interrupts enabled, which means that we'll potentially get better sample quality from performance monitor interrupts. - Timer, decrementer and doorbell interrupts now hard-enable shortly after removing the source of the interrupt, which means they no longer run entirely hard disabled. Again, this will improve perf sample quality. - On Book3E 64-bit, we now make the performance monitor interrupt act as an NMI like Book3S (the necessary C code for that to work appear to already be present in the FSL perf code, notably calling nmi_enter instead of irq_enter). (This also fixes a bug where BookE perfmon interrupts could clobber r14 ... oops) - We could make "masked" decrementer interrupts act as NMIs when doing timer-based perf sampling to improve the sample quality. Signed-off-by-yet: Benjamin Herrenschmidt <benh@kernel.crashing.org> --- v2: - Add hard-enable to decrementer, timer and doorbells - Fix CR clobber in masked irq handling on BookE - Make embedded perf interrupt act as an NMI - Add a PACA_HAPPENED_EE_EDGE for use by FSL if they want to retrigger an interrupt without preventing hard-enable v3: - Fix or vs. ori bug on Book3E - Fix enabling of interrupts for some exceptions on Book3E v4: - Fix resend of doorbells on return from interrupt on Book3E v5: - Rebased on top of my latest series, which involves some significant rework of some aspects of the patch. v6: - 32-bit compile fix - more compile fixes with various .config combos - factor out the asm code to soft-disable interrupts - remove the C wrapper around preempt_schedule_irq v7: - Fix a bug with hard irq state tracking on native power7
2012-03-06 15:27:59 +08:00
lis r10,0x7fff; \
ori r10,r10,0xffff; \
mtspr SPRN_DEC,r10; \
b 2f; \
1: cmpwi r10,PACA_IRQ_DBELL; \
beq 2f; \
cmpwi r10,PACA_IRQ_HMI; \
beq 2f; \
mfspr r10,SPRN_##_H##SRR1; \
powerpc: Rework lazy-interrupt handling The current implementation of lazy interrupts handling has some issues that this tries to address. We don't do the various workarounds we need to do when re-enabling interrupts in some cases such as when returning from an interrupt and thus we may still lose or get delayed decrementer or doorbell interrupts. The current scheme also makes it much harder to handle the external "edge" interrupts provided by some BookE processors when using the EPR facility (External Proxy) and the Freescale Hypervisor. Additionally, we tend to keep interrupts hard disabled in a number of cases, such as decrementer interrupts, external interrupts, or when a masked decrementer interrupt is pending. This is sub-optimal. This is an attempt at fixing it all in one go by reworking the way we do the lazy interrupt disabling from the ground up. The base idea is to replace the "hard_enabled" field with a "irq_happened" field in which we store a bit mask of what interrupt occurred while soft-disabled. When re-enabling, either via arch_local_irq_restore() or when returning from an interrupt, we can now decide what to do by testing bits in that field. We then implement replaying of the missed interrupts either by re-using the existing exception frame (in exception exit case) or via the creation of a new one from an assembly trampoline (in the arch_local_irq_enable case). This removes the need to play with the decrementer to try to create fake interrupts, among others. In addition, this adds a few refinements: - We no longer hard disable decrementer interrupts that occur while soft-disabled. We now simply bump the decrementer back to max (on BookS) or leave it stopped (on BookE) and continue with hard interrupts enabled, which means that we'll potentially get better sample quality from performance monitor interrupts. - Timer, decrementer and doorbell interrupts now hard-enable shortly after removing the source of the interrupt, which means they no longer run entirely hard disabled. Again, this will improve perf sample quality. - On Book3E 64-bit, we now make the performance monitor interrupt act as an NMI like Book3S (the necessary C code for that to work appear to already be present in the FSL perf code, notably calling nmi_enter instead of irq_enter). (This also fixes a bug where BookE perfmon interrupts could clobber r14 ... oops) - We could make "masked" decrementer interrupts act as NMIs when doing timer-based perf sampling to improve the sample quality. Signed-off-by-yet: Benjamin Herrenschmidt <benh@kernel.crashing.org> --- v2: - Add hard-enable to decrementer, timer and doorbells - Fix CR clobber in masked irq handling on BookE - Make embedded perf interrupt act as an NMI - Add a PACA_HAPPENED_EE_EDGE for use by FSL if they want to retrigger an interrupt without preventing hard-enable v3: - Fix or vs. ori bug on Book3E - Fix enabling of interrupts for some exceptions on Book3E v4: - Fix resend of doorbells on return from interrupt on Book3E v5: - Rebased on top of my latest series, which involves some significant rework of some aspects of the patch. v6: - 32-bit compile fix - more compile fixes with various .config combos - factor out the asm code to soft-disable interrupts - remove the C wrapper around preempt_schedule_irq v7: - Fix a bug with hard irq state tracking on native power7
2012-03-06 15:27:59 +08:00
rldicl r10,r10,48,1; /* clear MSR_EE */ \
rotldi r10,r10,16; \
mtspr SPRN_##_H##SRR1,r10; \
2: mtcrf 0x80,r9; \
ld r9,PACA_EXGEN+EX_R9(r13); \
ld r10,PACA_EXGEN+EX_R10(r13); \
ld r11,PACA_EXGEN+EX_R11(r13); \
GET_SCRATCH0(r13); \
##_H##rfid; \
b .
powerpc: Rework lazy-interrupt handling The current implementation of lazy interrupts handling has some issues that this tries to address. We don't do the various workarounds we need to do when re-enabling interrupts in some cases such as when returning from an interrupt and thus we may still lose or get delayed decrementer or doorbell interrupts. The current scheme also makes it much harder to handle the external "edge" interrupts provided by some BookE processors when using the EPR facility (External Proxy) and the Freescale Hypervisor. Additionally, we tend to keep interrupts hard disabled in a number of cases, such as decrementer interrupts, external interrupts, or when a masked decrementer interrupt is pending. This is sub-optimal. This is an attempt at fixing it all in one go by reworking the way we do the lazy interrupt disabling from the ground up. The base idea is to replace the "hard_enabled" field with a "irq_happened" field in which we store a bit mask of what interrupt occurred while soft-disabled. When re-enabling, either via arch_local_irq_restore() or when returning from an interrupt, we can now decide what to do by testing bits in that field. We then implement replaying of the missed interrupts either by re-using the existing exception frame (in exception exit case) or via the creation of a new one from an assembly trampoline (in the arch_local_irq_enable case). This removes the need to play with the decrementer to try to create fake interrupts, among others. In addition, this adds a few refinements: - We no longer hard disable decrementer interrupts that occur while soft-disabled. We now simply bump the decrementer back to max (on BookS) or leave it stopped (on BookE) and continue with hard interrupts enabled, which means that we'll potentially get better sample quality from performance monitor interrupts. - Timer, decrementer and doorbell interrupts now hard-enable shortly after removing the source of the interrupt, which means they no longer run entirely hard disabled. Again, this will improve perf sample quality. - On Book3E 64-bit, we now make the performance monitor interrupt act as an NMI like Book3S (the necessary C code for that to work appear to already be present in the FSL perf code, notably calling nmi_enter instead of irq_enter). (This also fixes a bug where BookE perfmon interrupts could clobber r14 ... oops) - We could make "masked" decrementer interrupts act as NMIs when doing timer-based perf sampling to improve the sample quality. Signed-off-by-yet: Benjamin Herrenschmidt <benh@kernel.crashing.org> --- v2: - Add hard-enable to decrementer, timer and doorbells - Fix CR clobber in masked irq handling on BookE - Make embedded perf interrupt act as an NMI - Add a PACA_HAPPENED_EE_EDGE for use by FSL if they want to retrigger an interrupt without preventing hard-enable v3: - Fix or vs. ori bug on Book3E - Fix enabling of interrupts for some exceptions on Book3E v4: - Fix resend of doorbells on return from interrupt on Book3E v5: - Rebased on top of my latest series, which involves some significant rework of some aspects of the patch. v6: - 32-bit compile fix - more compile fixes with various .config combos - factor out the asm code to soft-disable interrupts - remove the C wrapper around preempt_schedule_irq v7: - Fix a bug with hard irq state tracking on native power7
2012-03-06 15:27:59 +08:00
MASKED_INTERRUPT()
MASKED_INTERRUPT(H)
powerpc: Rework lazy-interrupt handling The current implementation of lazy interrupts handling has some issues that this tries to address. We don't do the various workarounds we need to do when re-enabling interrupts in some cases such as when returning from an interrupt and thus we may still lose or get delayed decrementer or doorbell interrupts. The current scheme also makes it much harder to handle the external "edge" interrupts provided by some BookE processors when using the EPR facility (External Proxy) and the Freescale Hypervisor. Additionally, we tend to keep interrupts hard disabled in a number of cases, such as decrementer interrupts, external interrupts, or when a masked decrementer interrupt is pending. This is sub-optimal. This is an attempt at fixing it all in one go by reworking the way we do the lazy interrupt disabling from the ground up. The base idea is to replace the "hard_enabled" field with a "irq_happened" field in which we store a bit mask of what interrupt occurred while soft-disabled. When re-enabling, either via arch_local_irq_restore() or when returning from an interrupt, we can now decide what to do by testing bits in that field. We then implement replaying of the missed interrupts either by re-using the existing exception frame (in exception exit case) or via the creation of a new one from an assembly trampoline (in the arch_local_irq_enable case). This removes the need to play with the decrementer to try to create fake interrupts, among others. In addition, this adds a few refinements: - We no longer hard disable decrementer interrupts that occur while soft-disabled. We now simply bump the decrementer back to max (on BookS) or leave it stopped (on BookE) and continue with hard interrupts enabled, which means that we'll potentially get better sample quality from performance monitor interrupts. - Timer, decrementer and doorbell interrupts now hard-enable shortly after removing the source of the interrupt, which means they no longer run entirely hard disabled. Again, this will improve perf sample quality. - On Book3E 64-bit, we now make the performance monitor interrupt act as an NMI like Book3S (the necessary C code for that to work appear to already be present in the FSL perf code, notably calling nmi_enter instead of irq_enter). (This also fixes a bug where BookE perfmon interrupts could clobber r14 ... oops) - We could make "masked" decrementer interrupts act as NMIs when doing timer-based perf sampling to improve the sample quality. Signed-off-by-yet: Benjamin Herrenschmidt <benh@kernel.crashing.org> --- v2: - Add hard-enable to decrementer, timer and doorbells - Fix CR clobber in masked irq handling on BookE - Make embedded perf interrupt act as an NMI - Add a PACA_HAPPENED_EE_EDGE for use by FSL if they want to retrigger an interrupt without preventing hard-enable v3: - Fix or vs. ori bug on Book3E - Fix enabling of interrupts for some exceptions on Book3E v4: - Fix resend of doorbells on return from interrupt on Book3E v5: - Rebased on top of my latest series, which involves some significant rework of some aspects of the patch. v6: - 32-bit compile fix - more compile fixes with various .config combos - factor out the asm code to soft-disable interrupts - remove the C wrapper around preempt_schedule_irq v7: - Fix a bug with hard irq state tracking on native power7
2012-03-06 15:27:59 +08:00
/*
* Called from arch_local_irq_enable when an interrupt needs
* to be resent. r3 contains 0x500, 0x900, 0xa00 or 0xe80 to indicate
* which kind of interrupt. MSR:EE is already off. We generate a
powerpc: Rework lazy-interrupt handling The current implementation of lazy interrupts handling has some issues that this tries to address. We don't do the various workarounds we need to do when re-enabling interrupts in some cases such as when returning from an interrupt and thus we may still lose or get delayed decrementer or doorbell interrupts. The current scheme also makes it much harder to handle the external "edge" interrupts provided by some BookE processors when using the EPR facility (External Proxy) and the Freescale Hypervisor. Additionally, we tend to keep interrupts hard disabled in a number of cases, such as decrementer interrupts, external interrupts, or when a masked decrementer interrupt is pending. This is sub-optimal. This is an attempt at fixing it all in one go by reworking the way we do the lazy interrupt disabling from the ground up. The base idea is to replace the "hard_enabled" field with a "irq_happened" field in which we store a bit mask of what interrupt occurred while soft-disabled. When re-enabling, either via arch_local_irq_restore() or when returning from an interrupt, we can now decide what to do by testing bits in that field. We then implement replaying of the missed interrupts either by re-using the existing exception frame (in exception exit case) or via the creation of a new one from an assembly trampoline (in the arch_local_irq_enable case). This removes the need to play with the decrementer to try to create fake interrupts, among others. In addition, this adds a few refinements: - We no longer hard disable decrementer interrupts that occur while soft-disabled. We now simply bump the decrementer back to max (on BookS) or leave it stopped (on BookE) and continue with hard interrupts enabled, which means that we'll potentially get better sample quality from performance monitor interrupts. - Timer, decrementer and doorbell interrupts now hard-enable shortly after removing the source of the interrupt, which means they no longer run entirely hard disabled. Again, this will improve perf sample quality. - On Book3E 64-bit, we now make the performance monitor interrupt act as an NMI like Book3S (the necessary C code for that to work appear to already be present in the FSL perf code, notably calling nmi_enter instead of irq_enter). (This also fixes a bug where BookE perfmon interrupts could clobber r14 ... oops) - We could make "masked" decrementer interrupts act as NMIs when doing timer-based perf sampling to improve the sample quality. Signed-off-by-yet: Benjamin Herrenschmidt <benh@kernel.crashing.org> --- v2: - Add hard-enable to decrementer, timer and doorbells - Fix CR clobber in masked irq handling on BookE - Make embedded perf interrupt act as an NMI - Add a PACA_HAPPENED_EE_EDGE for use by FSL if they want to retrigger an interrupt without preventing hard-enable v3: - Fix or vs. ori bug on Book3E - Fix enabling of interrupts for some exceptions on Book3E v4: - Fix resend of doorbells on return from interrupt on Book3E v5: - Rebased on top of my latest series, which involves some significant rework of some aspects of the patch. v6: - 32-bit compile fix - more compile fixes with various .config combos - factor out the asm code to soft-disable interrupts - remove the C wrapper around preempt_schedule_irq v7: - Fix a bug with hard irq state tracking on native power7
2012-03-06 15:27:59 +08:00
* stackframe like if a real interrupt had happened.
*
* Note: While MSR:EE is off, we need to make sure that _MSR
* in the generated frame has EE set to 1 or the exception
* handler will not properly re-enable them.
*/
_GLOBAL(__replay_interrupt)
/* We are going to jump to the exception common code which
* will retrieve various register values from the PACA which
* we don't give a damn about, so we don't bother storing them.
*/
mfmsr r12
mflr r11
mfcr r9
ori r12,r12,MSR_EE
cmpwi r3,0x900
beq decrementer_common
cmpwi r3,0x500
beq hardware_interrupt_common
BEGIN_FTR_SECTION
cmpwi r3,0xe80
beq h_doorbell_common
FTR_SECTION_ELSE
cmpwi r3,0xa00
beq doorbell_super_common
ALT_FTR_SECTION_END_IFSET(CPU_FTR_HVMODE)
blr
#ifdef CONFIG_PPC_PSERIES
/*
* Vectors for the FWNMI option. Share common code.
*/
.globl system_reset_fwnmi
.align 7
system_reset_fwnmi:
HMT_MEDIUM_PPR_DISCARD
SET_SCRATCH0(r13) /* save r13 */
EXCEPTION_PROLOG_PSERIES(PACA_EXGEN, system_reset_common, EXC_STD,
NOTEST, 0x100)
#endif /* CONFIG_PPC_PSERIES */
#ifdef __DISABLED__
/*
* This is used for when the SLB miss handler has to go virtual,
* which doesn't happen for now anymore but will once we re-implement
* dynamic VSIDs for shared page tables
*/
slb_miss_user_pseries:
std r10,PACA_EXGEN+EX_R10(r13)
std r11,PACA_EXGEN+EX_R11(r13)
std r12,PACA_EXGEN+EX_R12(r13)
GET_SCRATCH0(r10)
ld r11,PACA_EXSLB+EX_R9(r13)
ld r12,PACA_EXSLB+EX_R3(r13)
std r10,PACA_EXGEN+EX_R13(r13)
std r11,PACA_EXGEN+EX_R9(r13)
std r12,PACA_EXGEN+EX_R3(r13)
clrrdi r12,r13,32
mfmsr r10
mfspr r11,SRR0 /* save SRR0 */
ori r12,r12,slb_miss_user_common@l /* virt addr of handler */
ori r10,r10,MSR_IR|MSR_DR|MSR_RI
mtspr SRR0,r12
mfspr r12,SRR1 /* and SRR1 */
mtspr SRR1,r10
rfid
b . /* prevent spec. execution */
#endif /* __DISABLED__ */
#ifdef CONFIG_KVM_BOOK3S_64_HANDLER
kvmppc_skip_interrupt:
/*
* Here all GPRs are unchanged from when the interrupt happened
* except for r13, which is saved in SPRG_SCRATCH0.
*/
mfspr r13, SPRN_SRR0
addi r13, r13, 4
mtspr SPRN_SRR0, r13
GET_SCRATCH0(r13)
rfid
b .
kvmppc_skip_Hinterrupt:
/*
* Here all GPRs are unchanged from when the interrupt happened
* except for r13, which is saved in SPRG_SCRATCH0.
*/
mfspr r13, SPRN_HSRR0
addi r13, r13, 4
mtspr SPRN_HSRR0, r13
GET_SCRATCH0(r13)
hrfid
b .
#endif
/*
* Code from here down to __end_handlers is invoked from the
* exception prologs above. Because the prologs assemble the
* addresses of these handlers using the LOAD_HANDLER macro,
* which uses an ori instruction, these handlers must be in
* the first 64k of the kernel image.
*/
/*** Common interrupt handlers ***/
STD_EXCEPTION_COMMON(0x100, system_reset, system_reset_exception)
STD_EXCEPTION_COMMON_ASYNC(0x500, hardware_interrupt, do_IRQ)
STD_EXCEPTION_COMMON_ASYNC(0x900, decrementer, timer_interrupt)
STD_EXCEPTION_COMMON(0x980, hdecrementer, hdec_interrupt)
#ifdef CONFIG_PPC_DOORBELL
STD_EXCEPTION_COMMON_ASYNC(0xa00, doorbell_super, doorbell_exception)
#else
STD_EXCEPTION_COMMON_ASYNC(0xa00, doorbell_super, unknown_exception)
#endif
STD_EXCEPTION_COMMON(0xb00, trap_0b, unknown_exception)
STD_EXCEPTION_COMMON(0xd00, single_step, single_step_exception)
STD_EXCEPTION_COMMON(0xe00, trap_0e, unknown_exception)
STD_EXCEPTION_COMMON(0xe40, emulation_assist, emulation_assist_interrupt)
STD_EXCEPTION_COMMON_ASYNC(0xe60, hmi_exception, handle_hmi_exception)
#ifdef CONFIG_PPC_DOORBELL
STD_EXCEPTION_COMMON_ASYNC(0xe80, h_doorbell, doorbell_exception)
#else
STD_EXCEPTION_COMMON_ASYNC(0xe80, h_doorbell, unknown_exception)
#endif
STD_EXCEPTION_COMMON_ASYNC(0xf00, performance_monitor, performance_monitor_exception)
STD_EXCEPTION_COMMON(0x1300, instruction_breakpoint, instruction_breakpoint_exception)
STD_EXCEPTION_COMMON(0x1502, denorm, unknown_exception)
#ifdef CONFIG_ALTIVEC
STD_EXCEPTION_COMMON(0x1700, altivec_assist, altivec_assist_exception)
#else
STD_EXCEPTION_COMMON(0x1700, altivec_assist, unknown_exception)
#endif
#ifdef CONFIG_CBE_RAS
STD_EXCEPTION_COMMON(0x1200, cbe_system_error, cbe_system_error_exception)
STD_EXCEPTION_COMMON(0x1600, cbe_maintenance, cbe_maintenance_exception)
STD_EXCEPTION_COMMON(0x1800, cbe_thermal, cbe_thermal_exception)
#endif /* CONFIG_CBE_RAS */
/*
* Relocation-on interrupts: A subset of the interrupts can be delivered
* with IR=1/DR=1, if AIL==2 and MSR.HV won't be changed by delivering
* it. Addresses are the same as the original interrupt addresses, but
* offset by 0xc000000000004000.
* It's impossible to receive interrupts below 0x300 via this mechanism.
* KVM: None of these traps are from the guest ; anything that escalated
* to HV=1 from HV=0 is delivered via real mode handlers.
*/
/*
* This uses the standard macro, since the original 0x300 vector
* only has extra guff for STAB-based processors -- which never
* come here.
*/
STD_RELON_EXCEPTION_PSERIES(0x4300, 0x300, data_access)
. = 0x4380
.globl data_access_slb_relon_pSeries
data_access_slb_relon_pSeries:
SET_SCRATCH0(r13)
powerpc: Save CFAR before branching in interrupt entry paths Some of the interrupt vectors on 64-bit POWER server processors are only 32 bytes long, which is not enough for the full first-level interrupt handler. For these we currently just have a branch to an out-of-line handler. However, this means that we corrupt the CFAR (come-from address register) on POWER7 and later processors. To fix this, we split the EXCEPTION_PROLOG_1 macro into two pieces: EXCEPTION_PROLOG_0 contains the part up to the point where the CFAR is saved in the PACA, and EXCEPTION_PROLOG_1 contains the rest. We then put EXCEPTION_PROLOG_0 in the short interrupt vectors before we branch to the out-of-line handler, which contains the rest of the first-level interrupt handler. To facilitate this, we define new _OOL (out of line) variants of STD_EXCEPTION_PSERIES, etc. In order to get EXCEPTION_PROLOG_0 to be short enough, i.e., no more than 6 instructions, it was necessary to move the stores that move the PPR and CFAR values into the PACA into __EXCEPTION_PROLOG_1 and to get rid of one of the two HMT_MEDIUM instructions. Previously there was a HMT_MEDIUM_PPR_DISCARD before the prolog, which was nop'd out on processors with the PPR (POWER7 and later), and then another HMT_MEDIUM inside the HMT_MEDIUM_PPR_SAVE macro call inside __EXCEPTION_PROLOG_1, which was nop'd out on processors without PPR. Now the HMT_MEDIUM inside EXCEPTION_PROLOG_0 is there unconditionally and the HMT_MEDIUM_PPR_DISCARD is not strictly necessary, although this leaves it in for the interrupt vectors where there is room for it. Previously we had a handler for hypervisor maintenance interrupts at 0xe50, which doesn't leave enough room for the vector for hypervisor emulation assist interrupts at 0xe40, since we need 8 instructions. The 0xe50 vector was only used on POWER6, as the HMI vector was moved to 0xe60 on POWER7. Since we don't support running in hypervisor mode on POWER6, we just remove the handler at 0xe50. This also changes denorm_exception_hv to use EXCEPTION_PROLOG_0 instead of open-coding it, and removes the HMT_MEDIUM_PPR_DISCARD from the relocation-on vectors (since any CPU that supports relocation-on interrupts also has the PPR). Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-02-05 02:10:15 +08:00
EXCEPTION_PROLOG_0(PACA_EXSLB)
EXCEPTION_PROLOG_1(PACA_EXSLB, NOTEST, 0x380)
std r3,PACA_EXSLB+EX_R3(r13)
mfspr r3,SPRN_DAR
mfspr r12,SPRN_SRR1
#ifndef CONFIG_RELOCATABLE
b slb_miss_realmode
#else
/*
* We can't just use a direct branch to slb_miss_realmode
* because the distance from here to there depends on where
* the kernel ends up being put.
*/
mfctr r11
ld r10,PACAKBASE(r13)
LOAD_HANDLER(r10, slb_miss_realmode)
mtctr r10
bctr
#endif
STD_RELON_EXCEPTION_PSERIES(0x4400, 0x400, instruction_access)
. = 0x4480
.globl instruction_access_slb_relon_pSeries
instruction_access_slb_relon_pSeries:
SET_SCRATCH0(r13)
powerpc: Save CFAR before branching in interrupt entry paths Some of the interrupt vectors on 64-bit POWER server processors are only 32 bytes long, which is not enough for the full first-level interrupt handler. For these we currently just have a branch to an out-of-line handler. However, this means that we corrupt the CFAR (come-from address register) on POWER7 and later processors. To fix this, we split the EXCEPTION_PROLOG_1 macro into two pieces: EXCEPTION_PROLOG_0 contains the part up to the point where the CFAR is saved in the PACA, and EXCEPTION_PROLOG_1 contains the rest. We then put EXCEPTION_PROLOG_0 in the short interrupt vectors before we branch to the out-of-line handler, which contains the rest of the first-level interrupt handler. To facilitate this, we define new _OOL (out of line) variants of STD_EXCEPTION_PSERIES, etc. In order to get EXCEPTION_PROLOG_0 to be short enough, i.e., no more than 6 instructions, it was necessary to move the stores that move the PPR and CFAR values into the PACA into __EXCEPTION_PROLOG_1 and to get rid of one of the two HMT_MEDIUM instructions. Previously there was a HMT_MEDIUM_PPR_DISCARD before the prolog, which was nop'd out on processors with the PPR (POWER7 and later), and then another HMT_MEDIUM inside the HMT_MEDIUM_PPR_SAVE macro call inside __EXCEPTION_PROLOG_1, which was nop'd out on processors without PPR. Now the HMT_MEDIUM inside EXCEPTION_PROLOG_0 is there unconditionally and the HMT_MEDIUM_PPR_DISCARD is not strictly necessary, although this leaves it in for the interrupt vectors where there is room for it. Previously we had a handler for hypervisor maintenance interrupts at 0xe50, which doesn't leave enough room for the vector for hypervisor emulation assist interrupts at 0xe40, since we need 8 instructions. The 0xe50 vector was only used on POWER6, as the HMI vector was moved to 0xe60 on POWER7. Since we don't support running in hypervisor mode on POWER6, we just remove the handler at 0xe50. This also changes denorm_exception_hv to use EXCEPTION_PROLOG_0 instead of open-coding it, and removes the HMT_MEDIUM_PPR_DISCARD from the relocation-on vectors (since any CPU that supports relocation-on interrupts also has the PPR). Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-02-05 02:10:15 +08:00
EXCEPTION_PROLOG_0(PACA_EXSLB)
EXCEPTION_PROLOG_1(PACA_EXSLB, NOTEST, 0x480)
std r3,PACA_EXSLB+EX_R3(r13)
mfspr r3,SPRN_SRR0 /* SRR0 is faulting address */
mfspr r12,SPRN_SRR1
#ifndef CONFIG_RELOCATABLE
b slb_miss_realmode
#else
mfctr r11
ld r10,PACAKBASE(r13)
LOAD_HANDLER(r10, slb_miss_realmode)
mtctr r10
bctr
#endif
. = 0x4500
.globl hardware_interrupt_relon_pSeries;
.globl hardware_interrupt_relon_hv;
hardware_interrupt_relon_pSeries:
hardware_interrupt_relon_hv:
BEGIN_FTR_SECTION
_MASKABLE_RELON_EXCEPTION_PSERIES(0x502, hardware_interrupt, EXC_HV, SOFTEN_TEST_HV)
FTR_SECTION_ELSE
_MASKABLE_RELON_EXCEPTION_PSERIES(0x500, hardware_interrupt, EXC_STD, SOFTEN_TEST_PR)
ALT_FTR_SECTION_END_IFSET(CPU_FTR_HVMODE)
STD_RELON_EXCEPTION_PSERIES(0x4600, 0x600, alignment)
STD_RELON_EXCEPTION_PSERIES(0x4700, 0x700, program_check)
STD_RELON_EXCEPTION_PSERIES(0x4800, 0x800, fp_unavailable)
MASKABLE_RELON_EXCEPTION_PSERIES(0x4900, 0x900, decrementer)
STD_RELON_EXCEPTION_HV(0x4980, 0x982, hdecrementer)
MASKABLE_RELON_EXCEPTION_PSERIES(0x4a00, 0xa00, doorbell_super)
STD_RELON_EXCEPTION_PSERIES(0x4b00, 0xb00, trap_0b)
. = 0x4c00
.globl system_call_relon_pSeries
system_call_relon_pSeries:
HMT_MEDIUM
SYSCALL_PSERIES_1
SYSCALL_PSERIES_2_DIRECT
SYSCALL_PSERIES_3
STD_RELON_EXCEPTION_PSERIES(0x4d00, 0xd00, single_step)
. = 0x4e00
b . /* Can't happen, see v2.07 Book III-S section 6.5 */
. = 0x4e20
b . /* Can't happen, see v2.07 Book III-S section 6.5 */
. = 0x4e40
emulation_assist_relon_trampoline:
powerpc: Save CFAR before branching in interrupt entry paths Some of the interrupt vectors on 64-bit POWER server processors are only 32 bytes long, which is not enough for the full first-level interrupt handler. For these we currently just have a branch to an out-of-line handler. However, this means that we corrupt the CFAR (come-from address register) on POWER7 and later processors. To fix this, we split the EXCEPTION_PROLOG_1 macro into two pieces: EXCEPTION_PROLOG_0 contains the part up to the point where the CFAR is saved in the PACA, and EXCEPTION_PROLOG_1 contains the rest. We then put EXCEPTION_PROLOG_0 in the short interrupt vectors before we branch to the out-of-line handler, which contains the rest of the first-level interrupt handler. To facilitate this, we define new _OOL (out of line) variants of STD_EXCEPTION_PSERIES, etc. In order to get EXCEPTION_PROLOG_0 to be short enough, i.e., no more than 6 instructions, it was necessary to move the stores that move the PPR and CFAR values into the PACA into __EXCEPTION_PROLOG_1 and to get rid of one of the two HMT_MEDIUM instructions. Previously there was a HMT_MEDIUM_PPR_DISCARD before the prolog, which was nop'd out on processors with the PPR (POWER7 and later), and then another HMT_MEDIUM inside the HMT_MEDIUM_PPR_SAVE macro call inside __EXCEPTION_PROLOG_1, which was nop'd out on processors without PPR. Now the HMT_MEDIUM inside EXCEPTION_PROLOG_0 is there unconditionally and the HMT_MEDIUM_PPR_DISCARD is not strictly necessary, although this leaves it in for the interrupt vectors where there is room for it. Previously we had a handler for hypervisor maintenance interrupts at 0xe50, which doesn't leave enough room for the vector for hypervisor emulation assist interrupts at 0xe40, since we need 8 instructions. The 0xe50 vector was only used on POWER6, as the HMI vector was moved to 0xe60 on POWER7. Since we don't support running in hypervisor mode on POWER6, we just remove the handler at 0xe50. This also changes denorm_exception_hv to use EXCEPTION_PROLOG_0 instead of open-coding it, and removes the HMT_MEDIUM_PPR_DISCARD from the relocation-on vectors (since any CPU that supports relocation-on interrupts also has the PPR). Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-02-05 02:10:15 +08:00
SET_SCRATCH0(r13)
EXCEPTION_PROLOG_0(PACA_EXGEN)
b emulation_assist_relon_hv
. = 0x4e60
b . /* Can't happen, see v2.07 Book III-S section 6.5 */
. = 0x4e80
h_doorbell_relon_trampoline:
powerpc: Save CFAR before branching in interrupt entry paths Some of the interrupt vectors on 64-bit POWER server processors are only 32 bytes long, which is not enough for the full first-level interrupt handler. For these we currently just have a branch to an out-of-line handler. However, this means that we corrupt the CFAR (come-from address register) on POWER7 and later processors. To fix this, we split the EXCEPTION_PROLOG_1 macro into two pieces: EXCEPTION_PROLOG_0 contains the part up to the point where the CFAR is saved in the PACA, and EXCEPTION_PROLOG_1 contains the rest. We then put EXCEPTION_PROLOG_0 in the short interrupt vectors before we branch to the out-of-line handler, which contains the rest of the first-level interrupt handler. To facilitate this, we define new _OOL (out of line) variants of STD_EXCEPTION_PSERIES, etc. In order to get EXCEPTION_PROLOG_0 to be short enough, i.e., no more than 6 instructions, it was necessary to move the stores that move the PPR and CFAR values into the PACA into __EXCEPTION_PROLOG_1 and to get rid of one of the two HMT_MEDIUM instructions. Previously there was a HMT_MEDIUM_PPR_DISCARD before the prolog, which was nop'd out on processors with the PPR (POWER7 and later), and then another HMT_MEDIUM inside the HMT_MEDIUM_PPR_SAVE macro call inside __EXCEPTION_PROLOG_1, which was nop'd out on processors without PPR. Now the HMT_MEDIUM inside EXCEPTION_PROLOG_0 is there unconditionally and the HMT_MEDIUM_PPR_DISCARD is not strictly necessary, although this leaves it in for the interrupt vectors where there is room for it. Previously we had a handler for hypervisor maintenance interrupts at 0xe50, which doesn't leave enough room for the vector for hypervisor emulation assist interrupts at 0xe40, since we need 8 instructions. The 0xe50 vector was only used on POWER6, as the HMI vector was moved to 0xe60 on POWER7. Since we don't support running in hypervisor mode on POWER6, we just remove the handler at 0xe50. This also changes denorm_exception_hv to use EXCEPTION_PROLOG_0 instead of open-coding it, and removes the HMT_MEDIUM_PPR_DISCARD from the relocation-on vectors (since any CPU that supports relocation-on interrupts also has the PPR). Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-02-05 02:10:15 +08:00
SET_SCRATCH0(r13)
EXCEPTION_PROLOG_0(PACA_EXGEN)
b h_doorbell_relon_hv
. = 0x4f00
performance_monitor_relon_pseries_trampoline:
powerpc: Save CFAR before branching in interrupt entry paths Some of the interrupt vectors on 64-bit POWER server processors are only 32 bytes long, which is not enough for the full first-level interrupt handler. For these we currently just have a branch to an out-of-line handler. However, this means that we corrupt the CFAR (come-from address register) on POWER7 and later processors. To fix this, we split the EXCEPTION_PROLOG_1 macro into two pieces: EXCEPTION_PROLOG_0 contains the part up to the point where the CFAR is saved in the PACA, and EXCEPTION_PROLOG_1 contains the rest. We then put EXCEPTION_PROLOG_0 in the short interrupt vectors before we branch to the out-of-line handler, which contains the rest of the first-level interrupt handler. To facilitate this, we define new _OOL (out of line) variants of STD_EXCEPTION_PSERIES, etc. In order to get EXCEPTION_PROLOG_0 to be short enough, i.e., no more than 6 instructions, it was necessary to move the stores that move the PPR and CFAR values into the PACA into __EXCEPTION_PROLOG_1 and to get rid of one of the two HMT_MEDIUM instructions. Previously there was a HMT_MEDIUM_PPR_DISCARD before the prolog, which was nop'd out on processors with the PPR (POWER7 and later), and then another HMT_MEDIUM inside the HMT_MEDIUM_PPR_SAVE macro call inside __EXCEPTION_PROLOG_1, which was nop'd out on processors without PPR. Now the HMT_MEDIUM inside EXCEPTION_PROLOG_0 is there unconditionally and the HMT_MEDIUM_PPR_DISCARD is not strictly necessary, although this leaves it in for the interrupt vectors where there is room for it. Previously we had a handler for hypervisor maintenance interrupts at 0xe50, which doesn't leave enough room for the vector for hypervisor emulation assist interrupts at 0xe40, since we need 8 instructions. The 0xe50 vector was only used on POWER6, as the HMI vector was moved to 0xe60 on POWER7. Since we don't support running in hypervisor mode on POWER6, we just remove the handler at 0xe50. This also changes denorm_exception_hv to use EXCEPTION_PROLOG_0 instead of open-coding it, and removes the HMT_MEDIUM_PPR_DISCARD from the relocation-on vectors (since any CPU that supports relocation-on interrupts also has the PPR). Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-02-05 02:10:15 +08:00
SET_SCRATCH0(r13)
EXCEPTION_PROLOG_0(PACA_EXGEN)
b performance_monitor_relon_pSeries
. = 0x4f20
altivec_unavailable_relon_pseries_trampoline:
powerpc: Save CFAR before branching in interrupt entry paths Some of the interrupt vectors on 64-bit POWER server processors are only 32 bytes long, which is not enough for the full first-level interrupt handler. For these we currently just have a branch to an out-of-line handler. However, this means that we corrupt the CFAR (come-from address register) on POWER7 and later processors. To fix this, we split the EXCEPTION_PROLOG_1 macro into two pieces: EXCEPTION_PROLOG_0 contains the part up to the point where the CFAR is saved in the PACA, and EXCEPTION_PROLOG_1 contains the rest. We then put EXCEPTION_PROLOG_0 in the short interrupt vectors before we branch to the out-of-line handler, which contains the rest of the first-level interrupt handler. To facilitate this, we define new _OOL (out of line) variants of STD_EXCEPTION_PSERIES, etc. In order to get EXCEPTION_PROLOG_0 to be short enough, i.e., no more than 6 instructions, it was necessary to move the stores that move the PPR and CFAR values into the PACA into __EXCEPTION_PROLOG_1 and to get rid of one of the two HMT_MEDIUM instructions. Previously there was a HMT_MEDIUM_PPR_DISCARD before the prolog, which was nop'd out on processors with the PPR (POWER7 and later), and then another HMT_MEDIUM inside the HMT_MEDIUM_PPR_SAVE macro call inside __EXCEPTION_PROLOG_1, which was nop'd out on processors without PPR. Now the HMT_MEDIUM inside EXCEPTION_PROLOG_0 is there unconditionally and the HMT_MEDIUM_PPR_DISCARD is not strictly necessary, although this leaves it in for the interrupt vectors where there is room for it. Previously we had a handler for hypervisor maintenance interrupts at 0xe50, which doesn't leave enough room for the vector for hypervisor emulation assist interrupts at 0xe40, since we need 8 instructions. The 0xe50 vector was only used on POWER6, as the HMI vector was moved to 0xe60 on POWER7. Since we don't support running in hypervisor mode on POWER6, we just remove the handler at 0xe50. This also changes denorm_exception_hv to use EXCEPTION_PROLOG_0 instead of open-coding it, and removes the HMT_MEDIUM_PPR_DISCARD from the relocation-on vectors (since any CPU that supports relocation-on interrupts also has the PPR). Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-02-05 02:10:15 +08:00
SET_SCRATCH0(r13)
EXCEPTION_PROLOG_0(PACA_EXGEN)
b altivec_unavailable_relon_pSeries
. = 0x4f40
vsx_unavailable_relon_pseries_trampoline:
powerpc: Save CFAR before branching in interrupt entry paths Some of the interrupt vectors on 64-bit POWER server processors are only 32 bytes long, which is not enough for the full first-level interrupt handler. For these we currently just have a branch to an out-of-line handler. However, this means that we corrupt the CFAR (come-from address register) on POWER7 and later processors. To fix this, we split the EXCEPTION_PROLOG_1 macro into two pieces: EXCEPTION_PROLOG_0 contains the part up to the point where the CFAR is saved in the PACA, and EXCEPTION_PROLOG_1 contains the rest. We then put EXCEPTION_PROLOG_0 in the short interrupt vectors before we branch to the out-of-line handler, which contains the rest of the first-level interrupt handler. To facilitate this, we define new _OOL (out of line) variants of STD_EXCEPTION_PSERIES, etc. In order to get EXCEPTION_PROLOG_0 to be short enough, i.e., no more than 6 instructions, it was necessary to move the stores that move the PPR and CFAR values into the PACA into __EXCEPTION_PROLOG_1 and to get rid of one of the two HMT_MEDIUM instructions. Previously there was a HMT_MEDIUM_PPR_DISCARD before the prolog, which was nop'd out on processors with the PPR (POWER7 and later), and then another HMT_MEDIUM inside the HMT_MEDIUM_PPR_SAVE macro call inside __EXCEPTION_PROLOG_1, which was nop'd out on processors without PPR. Now the HMT_MEDIUM inside EXCEPTION_PROLOG_0 is there unconditionally and the HMT_MEDIUM_PPR_DISCARD is not strictly necessary, although this leaves it in for the interrupt vectors where there is room for it. Previously we had a handler for hypervisor maintenance interrupts at 0xe50, which doesn't leave enough room for the vector for hypervisor emulation assist interrupts at 0xe40, since we need 8 instructions. The 0xe50 vector was only used on POWER6, as the HMI vector was moved to 0xe60 on POWER7. Since we don't support running in hypervisor mode on POWER6, we just remove the handler at 0xe50. This also changes denorm_exception_hv to use EXCEPTION_PROLOG_0 instead of open-coding it, and removes the HMT_MEDIUM_PPR_DISCARD from the relocation-on vectors (since any CPU that supports relocation-on interrupts also has the PPR). Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-02-05 02:10:15 +08:00
SET_SCRATCH0(r13)
EXCEPTION_PROLOG_0(PACA_EXGEN)
b vsx_unavailable_relon_pSeries
. = 0x4f60
facility_unavailable_relon_trampoline:
SET_SCRATCH0(r13)
EXCEPTION_PROLOG_0(PACA_EXGEN)
b facility_unavailable_relon_pSeries
. = 0x4f80
hv_facility_unavailable_relon_trampoline:
SET_SCRATCH0(r13)
EXCEPTION_PROLOG_0(PACA_EXGEN)
b hv_facility_unavailable_relon_hv
STD_RELON_EXCEPTION_PSERIES(0x5300, 0x1300, instruction_breakpoint)
#ifdef CONFIG_PPC_DENORMALISATION
. = 0x5500
b denorm_exception_hv
#endif
STD_RELON_EXCEPTION_PSERIES(0x5700, 0x1700, altivec_assist)
/* Other future vectors */
.align 7
.globl __end_interrupts
__end_interrupts:
.align 7
system_call_entry_direct:
#if defined(CONFIG_RELOCATABLE)
/* The first level prologue may have used LR to get here, saving
* orig in r10. To save hacking/ifdeffing common code, restore here.
*/
mtlr r10
#endif
system_call_entry:
b system_call_common
ppc64_runlatch_on_trampoline:
b __ppc64_runlatch_on
/*
* Here r13 points to the paca, r9 contains the saved CR,
* SRR0 and SRR1 are saved in r11 and r12,
* r9 - r13 are saved in paca->exgen.
*/
.align 7
.globl data_access_common
data_access_common:
mfspr r10,SPRN_DAR
std r10,PACA_EXGEN+EX_DAR(r13)
mfspr r10,SPRN_DSISR
stw r10,PACA_EXGEN+EX_DSISR(r13)
EXCEPTION_PROLOG_COMMON(0x300, PACA_EXGEN)
RECONCILE_IRQ_STATE(r10, r11)
ld r12,_MSR(r1)
ld r3,PACA_EXGEN+EX_DAR(r13)
lwz r4,PACA_EXGEN+EX_DSISR(r13)
li r5,0x300
b do_hash_page /* Try to handle as hpte fault */
.align 7
.globl h_data_storage_common
h_data_storage_common:
mfspr r10,SPRN_HDAR
std r10,PACA_EXGEN+EX_DAR(r13)
mfspr r10,SPRN_HDSISR
stw r10,PACA_EXGEN+EX_DSISR(r13)
EXCEPTION_PROLOG_COMMON(0xe00, PACA_EXGEN)
bl save_nvgprs
RECONCILE_IRQ_STATE(r10, r11)
addi r3,r1,STACK_FRAME_OVERHEAD
bl unknown_exception
b ret_from_except
.align 7
.globl instruction_access_common
instruction_access_common:
EXCEPTION_PROLOG_COMMON(0x400, PACA_EXGEN)
RECONCILE_IRQ_STATE(r10, r11)
ld r12,_MSR(r1)
ld r3,_NIP(r1)
andis. r4,r12,0x5820
li r5,0x400
b do_hash_page /* Try to handle as hpte fault */
STD_EXCEPTION_COMMON(0xe20, h_instr_storage, unknown_exception)
/*
* Here is the common SLB miss user that is used when going to virtual
* mode for SLB misses, that is currently not used
*/
#ifdef __DISABLED__
.align 7
.globl slb_miss_user_common
slb_miss_user_common:
mflr r10
std r3,PACA_EXGEN+EX_DAR(r13)
stw r9,PACA_EXGEN+EX_CCR(r13)
std r10,PACA_EXGEN+EX_LR(r13)
std r11,PACA_EXGEN+EX_SRR0(r13)
bl slb_allocate_user
ld r10,PACA_EXGEN+EX_LR(r13)
ld r3,PACA_EXGEN+EX_R3(r13)
lwz r9,PACA_EXGEN+EX_CCR(r13)
ld r11,PACA_EXGEN+EX_SRR0(r13)
mtlr r10
beq- slb_miss_fault
andi. r10,r12,MSR_RI /* check for unrecoverable exception */
beq- unrecov_user_slb
mfmsr r10
.machine push
.machine "power4"
mtcrf 0x80,r9
.machine pop
clrrdi r10,r10,2 /* clear RI before setting SRR0/1 */
mtmsrd r10,1
mtspr SRR0,r11
mtspr SRR1,r12
ld r9,PACA_EXGEN+EX_R9(r13)
ld r10,PACA_EXGEN+EX_R10(r13)
ld r11,PACA_EXGEN+EX_R11(r13)
ld r12,PACA_EXGEN+EX_R12(r13)
ld r13,PACA_EXGEN+EX_R13(r13)
rfid
b .
slb_miss_fault:
EXCEPTION_PROLOG_COMMON(0x380, PACA_EXGEN)
ld r4,PACA_EXGEN+EX_DAR(r13)
li r5,0
std r4,_DAR(r1)
std r5,_DSISR(r1)
b handle_page_fault
unrecov_user_slb:
EXCEPTION_PROLOG_COMMON(0x4200, PACA_EXGEN)
RECONCILE_IRQ_STATE(r10, r11)
bl save_nvgprs
1: addi r3,r1,STACK_FRAME_OVERHEAD
bl unrecoverable_exception
b 1b
#endif /* __DISABLED__ */
powerpc: Fix "attempt to move .org backwards" error With recent machine check patch series changes, The exception vectors starting from 0x4300 are now overflowing with allyesconfig. Fix that by moving machine_check_common and machine_check_handle_early code out of that region to make enough room for exception vector area. Fixes this build error reportes by Stephen: arch/powerpc/kernel/exceptions-64s.S: Assembler messages: arch/powerpc/kernel/exceptions-64s.S:958: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:959: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:983: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:984: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1003: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1013: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1014: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1015: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1016: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1017: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1018: Error: attempt to move .org backwards [Moved the code further down as it introduced link errors due to too long relative branches to the masked interrupts handlers from the exception prologs. Also removed the useless feature section --BenH ] Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Tested-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-12-10 03:10:15 +08:00
/*
* Machine check is different because we use a different
* save area: PACA_EXMC instead of PACA_EXGEN.
*/
.align 7
.globl machine_check_common
machine_check_common:
mfspr r10,SPRN_DAR
std r10,PACA_EXGEN+EX_DAR(r13)
mfspr r10,SPRN_DSISR
stw r10,PACA_EXGEN+EX_DSISR(r13)
EXCEPTION_PROLOG_COMMON(0x200, PACA_EXMC)
FINISH_NAP
RECONCILE_IRQ_STATE(r10, r11)
powerpc: Fix "attempt to move .org backwards" error With recent machine check patch series changes, The exception vectors starting from 0x4300 are now overflowing with allyesconfig. Fix that by moving machine_check_common and machine_check_handle_early code out of that region to make enough room for exception vector area. Fixes this build error reportes by Stephen: arch/powerpc/kernel/exceptions-64s.S: Assembler messages: arch/powerpc/kernel/exceptions-64s.S:958: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:959: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:983: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:984: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1003: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1013: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1014: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1015: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1016: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1017: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1018: Error: attempt to move .org backwards [Moved the code further down as it introduced link errors due to too long relative branches to the masked interrupts handlers from the exception prologs. Also removed the useless feature section --BenH ] Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Tested-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-12-10 03:10:15 +08:00
ld r3,PACA_EXGEN+EX_DAR(r13)
lwz r4,PACA_EXGEN+EX_DSISR(r13)
std r3,_DAR(r1)
std r4,_DSISR(r1)
bl save_nvgprs
powerpc: Fix "attempt to move .org backwards" error With recent machine check patch series changes, The exception vectors starting from 0x4300 are now overflowing with allyesconfig. Fix that by moving machine_check_common and machine_check_handle_early code out of that region to make enough room for exception vector area. Fixes this build error reportes by Stephen: arch/powerpc/kernel/exceptions-64s.S: Assembler messages: arch/powerpc/kernel/exceptions-64s.S:958: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:959: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:983: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:984: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1003: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1013: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1014: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1015: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1016: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1017: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1018: Error: attempt to move .org backwards [Moved the code further down as it introduced link errors due to too long relative branches to the masked interrupts handlers from the exception prologs. Also removed the useless feature section --BenH ] Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Tested-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-12-10 03:10:15 +08:00
addi r3,r1,STACK_FRAME_OVERHEAD
bl machine_check_exception
b ret_from_except
powerpc: Fix "attempt to move .org backwards" error With recent machine check patch series changes, The exception vectors starting from 0x4300 are now overflowing with allyesconfig. Fix that by moving machine_check_common and machine_check_handle_early code out of that region to make enough room for exception vector area. Fixes this build error reportes by Stephen: arch/powerpc/kernel/exceptions-64s.S: Assembler messages: arch/powerpc/kernel/exceptions-64s.S:958: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:959: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:983: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:984: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1003: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1013: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1014: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1015: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1016: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1017: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1018: Error: attempt to move .org backwards [Moved the code further down as it introduced link errors due to too long relative branches to the masked interrupts handlers from the exception prologs. Also removed the useless feature section --BenH ] Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Tested-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-12-10 03:10:15 +08:00
.align 7
.globl alignment_common
alignment_common:
mfspr r10,SPRN_DAR
std r10,PACA_EXGEN+EX_DAR(r13)
mfspr r10,SPRN_DSISR
stw r10,PACA_EXGEN+EX_DSISR(r13)
EXCEPTION_PROLOG_COMMON(0x600, PACA_EXGEN)
ld r3,PACA_EXGEN+EX_DAR(r13)
lwz r4,PACA_EXGEN+EX_DSISR(r13)
std r3,_DAR(r1)
std r4,_DSISR(r1)
bl save_nvgprs
RECONCILE_IRQ_STATE(r10, r11)
addi r3,r1,STACK_FRAME_OVERHEAD
bl alignment_exception
b ret_from_except
.align 7
.globl program_check_common
program_check_common:
EXCEPTION_PROLOG_COMMON(0x700, PACA_EXGEN)
bl save_nvgprs
RECONCILE_IRQ_STATE(r10, r11)
addi r3,r1,STACK_FRAME_OVERHEAD
bl program_check_exception
b ret_from_except
.align 7
.globl fp_unavailable_common
fp_unavailable_common:
EXCEPTION_PROLOG_COMMON(0x800, PACA_EXGEN)
bne 1f /* if from user, just load it up */
bl save_nvgprs
RECONCILE_IRQ_STATE(r10, r11)
addi r3,r1,STACK_FRAME_OVERHEAD
bl kernel_fp_unavailable_exception
BUG_OPCODE
1:
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
BEGIN_FTR_SECTION
/* Test if 2 TM state bits are zero. If non-zero (ie. userspace was in
* transaction), go do TM stuff
*/
rldicl. r0, r12, (64-MSR_TS_LG), (64-2)
bne- 2f
END_FTR_SECTION_IFSET(CPU_FTR_TM)
#endif
bl load_up_fpu
b fast_exception_return
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
2: /* User process was in a transaction */
bl save_nvgprs
RECONCILE_IRQ_STATE(r10, r11)
addi r3,r1,STACK_FRAME_OVERHEAD
bl fp_unavailable_tm
b ret_from_except
#endif
.align 7
.globl altivec_unavailable_common
altivec_unavailable_common:
EXCEPTION_PROLOG_COMMON(0xf20, PACA_EXGEN)
#ifdef CONFIG_ALTIVEC
BEGIN_FTR_SECTION
beq 1f
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
BEGIN_FTR_SECTION_NESTED(69)
/* Test if 2 TM state bits are zero. If non-zero (ie. userspace was in
* transaction), go do TM stuff
*/
rldicl. r0, r12, (64-MSR_TS_LG), (64-2)
bne- 2f
END_FTR_SECTION_NESTED(CPU_FTR_TM, CPU_FTR_TM, 69)
#endif
bl load_up_altivec
b fast_exception_return
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
2: /* User process was in a transaction */
bl save_nvgprs
RECONCILE_IRQ_STATE(r10, r11)
addi r3,r1,STACK_FRAME_OVERHEAD
bl altivec_unavailable_tm
b ret_from_except
#endif
1:
END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC)
#endif
bl save_nvgprs
RECONCILE_IRQ_STATE(r10, r11)
addi r3,r1,STACK_FRAME_OVERHEAD
bl altivec_unavailable_exception
b ret_from_except
.align 7
.globl vsx_unavailable_common
vsx_unavailable_common:
EXCEPTION_PROLOG_COMMON(0xf40, PACA_EXGEN)
#ifdef CONFIG_VSX
BEGIN_FTR_SECTION
powerpc: Rework lazy-interrupt handling The current implementation of lazy interrupts handling has some issues that this tries to address. We don't do the various workarounds we need to do when re-enabling interrupts in some cases such as when returning from an interrupt and thus we may still lose or get delayed decrementer or doorbell interrupts. The current scheme also makes it much harder to handle the external "edge" interrupts provided by some BookE processors when using the EPR facility (External Proxy) and the Freescale Hypervisor. Additionally, we tend to keep interrupts hard disabled in a number of cases, such as decrementer interrupts, external interrupts, or when a masked decrementer interrupt is pending. This is sub-optimal. This is an attempt at fixing it all in one go by reworking the way we do the lazy interrupt disabling from the ground up. The base idea is to replace the "hard_enabled" field with a "irq_happened" field in which we store a bit mask of what interrupt occurred while soft-disabled. When re-enabling, either via arch_local_irq_restore() or when returning from an interrupt, we can now decide what to do by testing bits in that field. We then implement replaying of the missed interrupts either by re-using the existing exception frame (in exception exit case) or via the creation of a new one from an assembly trampoline (in the arch_local_irq_enable case). This removes the need to play with the decrementer to try to create fake interrupts, among others. In addition, this adds a few refinements: - We no longer hard disable decrementer interrupts that occur while soft-disabled. We now simply bump the decrementer back to max (on BookS) or leave it stopped (on BookE) and continue with hard interrupts enabled, which means that we'll potentially get better sample quality from performance monitor interrupts. - Timer, decrementer and doorbell interrupts now hard-enable shortly after removing the source of the interrupt, which means they no longer run entirely hard disabled. Again, this will improve perf sample quality. - On Book3E 64-bit, we now make the performance monitor interrupt act as an NMI like Book3S (the necessary C code for that to work appear to already be present in the FSL perf code, notably calling nmi_enter instead of irq_enter). (This also fixes a bug where BookE perfmon interrupts could clobber r14 ... oops) - We could make "masked" decrementer interrupts act as NMIs when doing timer-based perf sampling to improve the sample quality. Signed-off-by-yet: Benjamin Herrenschmidt <benh@kernel.crashing.org> --- v2: - Add hard-enable to decrementer, timer and doorbells - Fix CR clobber in masked irq handling on BookE - Make embedded perf interrupt act as an NMI - Add a PACA_HAPPENED_EE_EDGE for use by FSL if they want to retrigger an interrupt without preventing hard-enable v3: - Fix or vs. ori bug on Book3E - Fix enabling of interrupts for some exceptions on Book3E v4: - Fix resend of doorbells on return from interrupt on Book3E v5: - Rebased on top of my latest series, which involves some significant rework of some aspects of the patch. v6: - 32-bit compile fix - more compile fixes with various .config combos - factor out the asm code to soft-disable interrupts - remove the C wrapper around preempt_schedule_irq v7: - Fix a bug with hard irq state tracking on native power7
2012-03-06 15:27:59 +08:00
beq 1f
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
BEGIN_FTR_SECTION_NESTED(69)
/* Test if 2 TM state bits are zero. If non-zero (ie. userspace was in
* transaction), go do TM stuff
*/
rldicl. r0, r12, (64-MSR_TS_LG), (64-2)
bne- 2f
END_FTR_SECTION_NESTED(CPU_FTR_TM, CPU_FTR_TM, 69)
#endif
b load_up_vsx
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
2: /* User process was in a transaction */
bl save_nvgprs
RECONCILE_IRQ_STATE(r10, r11)
addi r3,r1,STACK_FRAME_OVERHEAD
bl vsx_unavailable_tm
b ret_from_except
#endif
1:
END_FTR_SECTION_IFSET(CPU_FTR_VSX)
#endif
bl save_nvgprs
RECONCILE_IRQ_STATE(r10, r11)
addi r3,r1,STACK_FRAME_OVERHEAD
bl vsx_unavailable_exception
b ret_from_except
STD_EXCEPTION_COMMON(0xf60, facility_unavailable, facility_unavailable_exception)
STD_EXCEPTION_COMMON(0xf80, hv_facility_unavailable, facility_unavailable_exception)
.align 7
.globl __end_handlers
__end_handlers:
/* Equivalents to the above handlers for relocation-on interrupt vectors */
powerpc: Save CFAR before branching in interrupt entry paths Some of the interrupt vectors on 64-bit POWER server processors are only 32 bytes long, which is not enough for the full first-level interrupt handler. For these we currently just have a branch to an out-of-line handler. However, this means that we corrupt the CFAR (come-from address register) on POWER7 and later processors. To fix this, we split the EXCEPTION_PROLOG_1 macro into two pieces: EXCEPTION_PROLOG_0 contains the part up to the point where the CFAR is saved in the PACA, and EXCEPTION_PROLOG_1 contains the rest. We then put EXCEPTION_PROLOG_0 in the short interrupt vectors before we branch to the out-of-line handler, which contains the rest of the first-level interrupt handler. To facilitate this, we define new _OOL (out of line) variants of STD_EXCEPTION_PSERIES, etc. In order to get EXCEPTION_PROLOG_0 to be short enough, i.e., no more than 6 instructions, it was necessary to move the stores that move the PPR and CFAR values into the PACA into __EXCEPTION_PROLOG_1 and to get rid of one of the two HMT_MEDIUM instructions. Previously there was a HMT_MEDIUM_PPR_DISCARD before the prolog, which was nop'd out on processors with the PPR (POWER7 and later), and then another HMT_MEDIUM inside the HMT_MEDIUM_PPR_SAVE macro call inside __EXCEPTION_PROLOG_1, which was nop'd out on processors without PPR. Now the HMT_MEDIUM inside EXCEPTION_PROLOG_0 is there unconditionally and the HMT_MEDIUM_PPR_DISCARD is not strictly necessary, although this leaves it in for the interrupt vectors where there is room for it. Previously we had a handler for hypervisor maintenance interrupts at 0xe50, which doesn't leave enough room for the vector for hypervisor emulation assist interrupts at 0xe40, since we need 8 instructions. The 0xe50 vector was only used on POWER6, as the HMI vector was moved to 0xe60 on POWER7. Since we don't support running in hypervisor mode on POWER6, we just remove the handler at 0xe50. This also changes denorm_exception_hv to use EXCEPTION_PROLOG_0 instead of open-coding it, and removes the HMT_MEDIUM_PPR_DISCARD from the relocation-on vectors (since any CPU that supports relocation-on interrupts also has the PPR). Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-02-05 02:10:15 +08:00
STD_RELON_EXCEPTION_HV_OOL(0xe40, emulation_assist)
MASKABLE_RELON_EXCEPTION_HV_OOL(0xe80, h_doorbell)
powerpc: Save CFAR before branching in interrupt entry paths Some of the interrupt vectors on 64-bit POWER server processors are only 32 bytes long, which is not enough for the full first-level interrupt handler. For these we currently just have a branch to an out-of-line handler. However, this means that we corrupt the CFAR (come-from address register) on POWER7 and later processors. To fix this, we split the EXCEPTION_PROLOG_1 macro into two pieces: EXCEPTION_PROLOG_0 contains the part up to the point where the CFAR is saved in the PACA, and EXCEPTION_PROLOG_1 contains the rest. We then put EXCEPTION_PROLOG_0 in the short interrupt vectors before we branch to the out-of-line handler, which contains the rest of the first-level interrupt handler. To facilitate this, we define new _OOL (out of line) variants of STD_EXCEPTION_PSERIES, etc. In order to get EXCEPTION_PROLOG_0 to be short enough, i.e., no more than 6 instructions, it was necessary to move the stores that move the PPR and CFAR values into the PACA into __EXCEPTION_PROLOG_1 and to get rid of one of the two HMT_MEDIUM instructions. Previously there was a HMT_MEDIUM_PPR_DISCARD before the prolog, which was nop'd out on processors with the PPR (POWER7 and later), and then another HMT_MEDIUM inside the HMT_MEDIUM_PPR_SAVE macro call inside __EXCEPTION_PROLOG_1, which was nop'd out on processors without PPR. Now the HMT_MEDIUM inside EXCEPTION_PROLOG_0 is there unconditionally and the HMT_MEDIUM_PPR_DISCARD is not strictly necessary, although this leaves it in for the interrupt vectors where there is room for it. Previously we had a handler for hypervisor maintenance interrupts at 0xe50, which doesn't leave enough room for the vector for hypervisor emulation assist interrupts at 0xe40, since we need 8 instructions. The 0xe50 vector was only used on POWER6, as the HMI vector was moved to 0xe60 on POWER7. Since we don't support running in hypervisor mode on POWER6, we just remove the handler at 0xe50. This also changes denorm_exception_hv to use EXCEPTION_PROLOG_0 instead of open-coding it, and removes the HMT_MEDIUM_PPR_DISCARD from the relocation-on vectors (since any CPU that supports relocation-on interrupts also has the PPR). Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-02-05 02:10:15 +08:00
STD_RELON_EXCEPTION_PSERIES_OOL(0xf00, performance_monitor)
STD_RELON_EXCEPTION_PSERIES_OOL(0xf20, altivec_unavailable)
STD_RELON_EXCEPTION_PSERIES_OOL(0xf40, vsx_unavailable)
STD_RELON_EXCEPTION_PSERIES_OOL(0xf60, facility_unavailable)
STD_RELON_EXCEPTION_HV_OOL(0xf80, hv_facility_unavailable)
#if defined(CONFIG_PPC_PSERIES) || defined(CONFIG_PPC_POWERNV)
/*
* Data area reserved for FWNMI option.
* This address (0x7000) is fixed by the RPA.
*/
.= 0x7000
.globl fwnmi_data_area
fwnmi_data_area:
/* pseries and powernv need to keep the whole page from
* 0x7000 to 0x8000 free for use by the firmware
*/
. = 0x8000
#endif /* defined(CONFIG_PPC_PSERIES) || defined(CONFIG_PPC_POWERNV) */
.globl hmi_exception_early
hmi_exception_early:
EXCEPTION_PROLOG_1(PACA_EXGEN, NOTEST, 0xe60)
mr r10,r1 /* Save r1 */
ld r1,PACAEMERGSP(r13) /* Use emergency stack */
subi r1,r1,INT_FRAME_SIZE /* alloc stack frame */
std r9,_CCR(r1) /* save CR in stackframe */
mfspr r11,SPRN_HSRR0 /* Save HSRR0 */
std r11,_NIP(r1) /* save HSRR0 in stackframe */
mfspr r12,SPRN_HSRR1 /* Save SRR1 */
std r12,_MSR(r1) /* save SRR1 in stackframe */
std r10,0(r1) /* make stack chain pointer */
std r0,GPR0(r1) /* save r0 in stackframe */
std r10,GPR1(r1) /* save r1 in stackframe */
EXCEPTION_PROLOG_COMMON_2(PACA_EXGEN)
EXCEPTION_PROLOG_COMMON_3(0xe60)
addi r3,r1,STACK_FRAME_OVERHEAD
bl hmi_exception_realmode
/* Windup the stack. */
/* Move original HSRR0 and HSRR1 into the respective regs */
ld r9,_MSR(r1)
mtspr SPRN_HSRR1,r9
ld r3,_NIP(r1)
mtspr SPRN_HSRR0,r3
ld r9,_CTR(r1)
mtctr r9
ld r9,_XER(r1)
mtxer r9
ld r9,_LINK(r1)
mtlr r9
REST_GPR(0, r1)
REST_8GPRS(2, r1)
REST_GPR(10, r1)
ld r11,_CCR(r1)
mtcr r11
REST_GPR(11, r1)
REST_2GPRS(12, r1)
/* restore original r1. */
ld r1,GPR1(r1)
/*
* Go to virtual mode and pull the HMI event information from
* firmware.
*/
.globl hmi_exception_after_realmode
hmi_exception_after_realmode:
SET_SCRATCH0(r13)
EXCEPTION_PROLOG_0(PACA_EXGEN)
b hmi_exception_hv
#ifdef CONFIG_PPC_POWERNV
_GLOBAL(opal_mc_secondary_handler)
HMT_MEDIUM_PPR_DISCARD
SET_SCRATCH0(r13)
GET_PACA(r13)
clrldi r3,r3,2
tovirt(r3,r3)
std r3,PACA_OPAL_MC_EVT(r13)
ld r13,OPAL_MC_SRR0(r3)
mtspr SPRN_SRR0,r13
ld r13,OPAL_MC_SRR1(r3)
mtspr SPRN_SRR1,r13
ld r3,OPAL_MC_GPR3(r3)
GET_SCRATCH0(r13)
b machine_check_pSeries
#endif /* CONFIG_PPC_POWERNV */
powerpc: Fix "attempt to move .org backwards" error With recent machine check patch series changes, The exception vectors starting from 0x4300 are now overflowing with allyesconfig. Fix that by moving machine_check_common and machine_check_handle_early code out of that region to make enough room for exception vector area. Fixes this build error reportes by Stephen: arch/powerpc/kernel/exceptions-64s.S: Assembler messages: arch/powerpc/kernel/exceptions-64s.S:958: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:959: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:983: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:984: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1003: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1013: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1014: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1015: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1016: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1017: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1018: Error: attempt to move .org backwards [Moved the code further down as it introduced link errors due to too long relative branches to the masked interrupts handlers from the exception prologs. Also removed the useless feature section --BenH ] Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Tested-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-12-10 03:10:15 +08:00
#define MACHINE_CHECK_HANDLER_WINDUP \
/* Clear MSR_RI before setting SRR0 and SRR1. */\
li r0,MSR_RI; \
mfmsr r9; /* get MSR value */ \
andc r9,r9,r0; \
mtmsrd r9,1; /* Clear MSR_RI */ \
/* Move original SRR0 and SRR1 into the respective regs */ \
ld r9,_MSR(r1); \
mtspr SPRN_SRR1,r9; \
ld r3,_NIP(r1); \
mtspr SPRN_SRR0,r3; \
ld r9,_CTR(r1); \
mtctr r9; \
ld r9,_XER(r1); \
mtxer r9; \
ld r9,_LINK(r1); \
mtlr r9; \
REST_GPR(0, r1); \
REST_8GPRS(2, r1); \
REST_GPR(10, r1); \
ld r11,_CCR(r1); \
mtcr r11; \
/* Decrement paca->in_mce. */ \
lhz r12,PACA_IN_MCE(r13); \
subi r12,r12,1; \
sth r12,PACA_IN_MCE(r13); \
REST_GPR(11, r1); \
REST_2GPRS(12, r1); \
/* restore original r1. */ \
ld r1,GPR1(r1)
/*
* Handle machine check early in real mode. We come here with
* ME=1, MMU (IR=0 and DR=0) off and using MC emergency stack.
*/
.align 7
.globl machine_check_handle_early
machine_check_handle_early:
std r0,GPR0(r1) /* Save r0 */
EXCEPTION_PROLOG_COMMON_3(0x200)
bl save_nvgprs
powerpc: Fix "attempt to move .org backwards" error With recent machine check patch series changes, The exception vectors starting from 0x4300 are now overflowing with allyesconfig. Fix that by moving machine_check_common and machine_check_handle_early code out of that region to make enough room for exception vector area. Fixes this build error reportes by Stephen: arch/powerpc/kernel/exceptions-64s.S: Assembler messages: arch/powerpc/kernel/exceptions-64s.S:958: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:959: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:983: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:984: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1003: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1013: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1014: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1015: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1016: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1017: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1018: Error: attempt to move .org backwards [Moved the code further down as it introduced link errors due to too long relative branches to the masked interrupts handlers from the exception prologs. Also removed the useless feature section --BenH ] Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Tested-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-12-10 03:10:15 +08:00
addi r3,r1,STACK_FRAME_OVERHEAD
bl machine_check_early
powerpc/book3s: Fix machine check handling for unhandled errors Current code does not check for unhandled/unrecovered errors and return from interrupt if it is recoverable exception which in-turn triggers same machine check exception in a loop causing hypervisor to be unresponsive. This patch fixes this situation and forces hypervisor to panic for unhandled/unrecovered errors. This patch also fixes another issue where unrecoverable_exception routine was called in real mode in case of unrecoverable exception (MSR_RI = 0). This causes another exception vector 0x300 (data access) during system crash leading to confusion while debugging cause of the system crash. Also turn ME bit off while going down, so that when another MCE is hit during panic path, system will checkstop and hypervisor will get restarted cleanly by SP. With the above fixes we now throw correct console messages (see below) while crashing the system in case of unhandled/unrecoverable machine checks. -------------- Severe Machine check interrupt [[Not recovered] Initiator: CPU Error type: UE [Instruction fetch] Effective address: 0000000030002864 Oops: Machine check, sig: 7 [#1] SMP NR_CPUS=2048 NUMA PowerNV Modules linked in: bork(O) bridge stp llc kvm [last unloaded: bork] CPU: 36 PID: 55162 Comm: bash Tainted: G O 3.14.0mce #1 task: c000002d72d022d0 ti: c000000007ec0000 task.ti: c000002d72de4000 NIP: 0000000030002864 LR: 00000000300151a4 CTR: 000000003001518c REGS: c000000007ec3d80 TRAP: 0200 Tainted: G O (3.14.0mce) MSR: 9000000000041002 <SF,HV,ME,RI> CR: 28222848 XER: 20000000 CFAR: 0000000030002838 DAR: d0000000004d0000 DSISR: 00000000 SOFTE: 1 GPR00: 000000003001512c 0000000031f92cb0 0000000030078af0 0000000030002864 GPR04: d0000000004d0000 0000000000000000 0000000030002864 ffffffffffffffc9 GPR08: 0000000000000024 0000000030008af0 000000000000002c c00000000150e728 GPR12: 9000000000041002 0000000031f90000 0000000010142550 0000000040000000 GPR16: 0000000010143cdc 0000000000000000 00000000101306fc 00000000101424dc GPR20: 00000000101424e0 000000001013c6f0 0000000000000000 0000000000000000 GPR24: 0000000010143ce0 00000000100f6440 c000002d72de7e00 c000002d72860250 GPR28: c000002d72860240 c000002d72ac0038 0000000000000008 0000000000040000 NIP [0000000030002864] 0x30002864 LR [00000000300151a4] 0x300151a4 Call Trace: Instruction dump: XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX ---[ end trace 7285f0beac1e29d3 ]--- Sending IPI to other CPUs IPI complete OPAL V3 detected ! -------------- Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-06-11 16:47:56 +08:00
std r3,RESULT(r1) /* Save result */
powerpc: Fix "attempt to move .org backwards" error With recent machine check patch series changes, The exception vectors starting from 0x4300 are now overflowing with allyesconfig. Fix that by moving machine_check_common and machine_check_handle_early code out of that region to make enough room for exception vector area. Fixes this build error reportes by Stephen: arch/powerpc/kernel/exceptions-64s.S: Assembler messages: arch/powerpc/kernel/exceptions-64s.S:958: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:959: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:983: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:984: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1003: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1013: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1014: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1015: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1016: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1017: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1018: Error: attempt to move .org backwards [Moved the code further down as it introduced link errors due to too long relative branches to the masked interrupts handlers from the exception prologs. Also removed the useless feature section --BenH ] Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Tested-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-12-10 03:10:15 +08:00
ld r12,_MSR(r1)
#ifdef CONFIG_PPC_P7_NAP
/*
* Check if thread was in power saving mode. We come here when any
* of the following is true:
* a. thread wasn't in power saving mode
* b. thread was in power saving mode with no state loss or
* supervisor state loss
*
* Go back to nap again if (b) is true.
*/
rlwinm. r11,r12,47-31,30,31 /* Was it in power saving mode? */
beq 4f /* No, it wasn;t */
/* Thread was in power saving mode. Go back to nap again. */
cmpwi r11,2
bne 3f
/* Supervisor state loss */
li r0,1
stb r0,PACA_NAPSTATELOST(r13)
3: bl machine_check_queue_event
powerpc: Fix "attempt to move .org backwards" error With recent machine check patch series changes, The exception vectors starting from 0x4300 are now overflowing with allyesconfig. Fix that by moving machine_check_common and machine_check_handle_early code out of that region to make enough room for exception vector area. Fixes this build error reportes by Stephen: arch/powerpc/kernel/exceptions-64s.S: Assembler messages: arch/powerpc/kernel/exceptions-64s.S:958: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:959: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:983: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:984: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1003: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1013: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1014: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1015: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1016: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1017: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1018: Error: attempt to move .org backwards [Moved the code further down as it introduced link errors due to too long relative branches to the masked interrupts handlers from the exception prologs. Also removed the useless feature section --BenH ] Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Tested-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-12-10 03:10:15 +08:00
MACHINE_CHECK_HANDLER_WINDUP
GET_PACA(r13)
ld r1,PACAR1(r13)
b power7_enter_nap_mode
powerpc: Fix "attempt to move .org backwards" error With recent machine check patch series changes, The exception vectors starting from 0x4300 are now overflowing with allyesconfig. Fix that by moving machine_check_common and machine_check_handle_early code out of that region to make enough room for exception vector area. Fixes this build error reportes by Stephen: arch/powerpc/kernel/exceptions-64s.S: Assembler messages: arch/powerpc/kernel/exceptions-64s.S:958: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:959: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:983: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:984: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1003: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1013: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1014: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1015: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1016: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1017: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1018: Error: attempt to move .org backwards [Moved the code further down as it introduced link errors due to too long relative branches to the masked interrupts handlers from the exception prologs. Also removed the useless feature section --BenH ] Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Tested-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-12-10 03:10:15 +08:00
4:
#endif
/*
* Check if we are coming from hypervisor userspace. If yes then we
* continue in host kernel in V mode to deliver the MC event.
*/
rldicl. r11,r12,4,63 /* See if MC hit while in HV mode. */
beq 5f
andi. r11,r12,MSR_PR /* See if coming from user. */
bne 9f /* continue in V mode if we are. */
5:
#ifdef CONFIG_KVM_BOOK3S_64_HV
/*
* We are coming from kernel context. Check if we are coming from
* guest. if yes, then we can continue. We will fall through
* do_kvm_200->kvmppc_interrupt to deliver the MC event to guest.
*/
lbz r11,HSTATE_IN_GUEST(r13)
cmpwi r11,0 /* Check if coming from guest */
bne 9f /* continue if we are. */
#endif
/*
* At this point we are not sure about what context we come from.
* Queue up the MCE event and return from the interrupt.
* But before that, check if this is an un-recoverable exception.
* If yes, then stay on emergency stack and panic.
*/
andi. r11,r12,MSR_RI
bne 2f
powerpc/book3s: Fix machine check handling for unhandled errors Current code does not check for unhandled/unrecovered errors and return from interrupt if it is recoverable exception which in-turn triggers same machine check exception in a loop causing hypervisor to be unresponsive. This patch fixes this situation and forces hypervisor to panic for unhandled/unrecovered errors. This patch also fixes another issue where unrecoverable_exception routine was called in real mode in case of unrecoverable exception (MSR_RI = 0). This causes another exception vector 0x300 (data access) during system crash leading to confusion while debugging cause of the system crash. Also turn ME bit off while going down, so that when another MCE is hit during panic path, system will checkstop and hypervisor will get restarted cleanly by SP. With the above fixes we now throw correct console messages (see below) while crashing the system in case of unhandled/unrecoverable machine checks. -------------- Severe Machine check interrupt [[Not recovered] Initiator: CPU Error type: UE [Instruction fetch] Effective address: 0000000030002864 Oops: Machine check, sig: 7 [#1] SMP NR_CPUS=2048 NUMA PowerNV Modules linked in: bork(O) bridge stp llc kvm [last unloaded: bork] CPU: 36 PID: 55162 Comm: bash Tainted: G O 3.14.0mce #1 task: c000002d72d022d0 ti: c000000007ec0000 task.ti: c000002d72de4000 NIP: 0000000030002864 LR: 00000000300151a4 CTR: 000000003001518c REGS: c000000007ec3d80 TRAP: 0200 Tainted: G O (3.14.0mce) MSR: 9000000000041002 <SF,HV,ME,RI> CR: 28222848 XER: 20000000 CFAR: 0000000030002838 DAR: d0000000004d0000 DSISR: 00000000 SOFTE: 1 GPR00: 000000003001512c 0000000031f92cb0 0000000030078af0 0000000030002864 GPR04: d0000000004d0000 0000000000000000 0000000030002864 ffffffffffffffc9 GPR08: 0000000000000024 0000000030008af0 000000000000002c c00000000150e728 GPR12: 9000000000041002 0000000031f90000 0000000010142550 0000000040000000 GPR16: 0000000010143cdc 0000000000000000 00000000101306fc 00000000101424dc GPR20: 00000000101424e0 000000001013c6f0 0000000000000000 0000000000000000 GPR24: 0000000010143ce0 00000000100f6440 c000002d72de7e00 c000002d72860250 GPR28: c000002d72860240 c000002d72ac0038 0000000000000008 0000000000040000 NIP [0000000030002864] 0x30002864 LR [00000000300151a4] 0x300151a4 Call Trace: Instruction dump: XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX ---[ end trace 7285f0beac1e29d3 ]--- Sending IPI to other CPUs IPI complete OPAL V3 detected ! -------------- Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-06-11 16:47:56 +08:00
1: mfspr r11,SPRN_SRR0
ld r10,PACAKBASE(r13)
LOAD_HANDLER(r10,unrecover_mce)
mtspr SPRN_SRR0,r10
ld r10,PACAKMSR(r13)
/*
* We are going down. But there are chances that we might get hit by
* another MCE during panic path and we may run into unstable state
* with no way out. Hence, turn ME bit off while going down, so that
* when another MCE is hit during panic path, system will checkstop
* and hypervisor will get restarted cleanly by SP.
*/
li r3,MSR_ME
andc r10,r10,r3 /* Turn off MSR_ME */
mtspr SPRN_SRR1,r10
rfid
b .
powerpc: Fix "attempt to move .org backwards" error With recent machine check patch series changes, The exception vectors starting from 0x4300 are now overflowing with allyesconfig. Fix that by moving machine_check_common and machine_check_handle_early code out of that region to make enough room for exception vector area. Fixes this build error reportes by Stephen: arch/powerpc/kernel/exceptions-64s.S: Assembler messages: arch/powerpc/kernel/exceptions-64s.S:958: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:959: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:983: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:984: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1003: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1013: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1014: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1015: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1016: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1017: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1018: Error: attempt to move .org backwards [Moved the code further down as it introduced link errors due to too long relative branches to the masked interrupts handlers from the exception prologs. Also removed the useless feature section --BenH ] Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Tested-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-12-10 03:10:15 +08:00
2:
powerpc/book3s: Fix machine check handling for unhandled errors Current code does not check for unhandled/unrecovered errors and return from interrupt if it is recoverable exception which in-turn triggers same machine check exception in a loop causing hypervisor to be unresponsive. This patch fixes this situation and forces hypervisor to panic for unhandled/unrecovered errors. This patch also fixes another issue where unrecoverable_exception routine was called in real mode in case of unrecoverable exception (MSR_RI = 0). This causes another exception vector 0x300 (data access) during system crash leading to confusion while debugging cause of the system crash. Also turn ME bit off while going down, so that when another MCE is hit during panic path, system will checkstop and hypervisor will get restarted cleanly by SP. With the above fixes we now throw correct console messages (see below) while crashing the system in case of unhandled/unrecoverable machine checks. -------------- Severe Machine check interrupt [[Not recovered] Initiator: CPU Error type: UE [Instruction fetch] Effective address: 0000000030002864 Oops: Machine check, sig: 7 [#1] SMP NR_CPUS=2048 NUMA PowerNV Modules linked in: bork(O) bridge stp llc kvm [last unloaded: bork] CPU: 36 PID: 55162 Comm: bash Tainted: G O 3.14.0mce #1 task: c000002d72d022d0 ti: c000000007ec0000 task.ti: c000002d72de4000 NIP: 0000000030002864 LR: 00000000300151a4 CTR: 000000003001518c REGS: c000000007ec3d80 TRAP: 0200 Tainted: G O (3.14.0mce) MSR: 9000000000041002 <SF,HV,ME,RI> CR: 28222848 XER: 20000000 CFAR: 0000000030002838 DAR: d0000000004d0000 DSISR: 00000000 SOFTE: 1 GPR00: 000000003001512c 0000000031f92cb0 0000000030078af0 0000000030002864 GPR04: d0000000004d0000 0000000000000000 0000000030002864 ffffffffffffffc9 GPR08: 0000000000000024 0000000030008af0 000000000000002c c00000000150e728 GPR12: 9000000000041002 0000000031f90000 0000000010142550 0000000040000000 GPR16: 0000000010143cdc 0000000000000000 00000000101306fc 00000000101424dc GPR20: 00000000101424e0 000000001013c6f0 0000000000000000 0000000000000000 GPR24: 0000000010143ce0 00000000100f6440 c000002d72de7e00 c000002d72860250 GPR28: c000002d72860240 c000002d72ac0038 0000000000000008 0000000000040000 NIP [0000000030002864] 0x30002864 LR [00000000300151a4] 0x300151a4 Call Trace: Instruction dump: XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX ---[ end trace 7285f0beac1e29d3 ]--- Sending IPI to other CPUs IPI complete OPAL V3 detected ! -------------- Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-06-11 16:47:56 +08:00
/*
* Check if we have successfully handled/recovered from error, if not
* then stay on emergency stack and panic.
*/
ld r3,RESULT(r1) /* Load result */
cmpdi r3,0 /* see if we handled MCE successfully */
beq 1b /* if !handled then panic */
powerpc: Fix "attempt to move .org backwards" error With recent machine check patch series changes, The exception vectors starting from 0x4300 are now overflowing with allyesconfig. Fix that by moving machine_check_common and machine_check_handle_early code out of that region to make enough room for exception vector area. Fixes this build error reportes by Stephen: arch/powerpc/kernel/exceptions-64s.S: Assembler messages: arch/powerpc/kernel/exceptions-64s.S:958: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:959: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:983: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:984: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1003: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1013: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1014: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1015: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1016: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1017: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1018: Error: attempt to move .org backwards [Moved the code further down as it introduced link errors due to too long relative branches to the masked interrupts handlers from the exception prologs. Also removed the useless feature section --BenH ] Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Tested-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-12-10 03:10:15 +08:00
/*
* Return from MC interrupt.
* Queue up the MCE event so that we can log it later, while
* returning from kernel or opal call.
*/
bl machine_check_queue_event
powerpc: Fix "attempt to move .org backwards" error With recent machine check patch series changes, The exception vectors starting from 0x4300 are now overflowing with allyesconfig. Fix that by moving machine_check_common and machine_check_handle_early code out of that region to make enough room for exception vector area. Fixes this build error reportes by Stephen: arch/powerpc/kernel/exceptions-64s.S: Assembler messages: arch/powerpc/kernel/exceptions-64s.S:958: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:959: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:983: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:984: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1003: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1013: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1014: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1015: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1016: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1017: Error: attempt to move .org backwards arch/powerpc/kernel/exceptions-64s.S:1018: Error: attempt to move .org backwards [Moved the code further down as it introduced link errors due to too long relative branches to the masked interrupts handlers from the exception prologs. Also removed the useless feature section --BenH ] Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Tested-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-12-10 03:10:15 +08:00
MACHINE_CHECK_HANDLER_WINDUP
rfid
9:
/* Deliver the machine check to host kernel in V mode. */
MACHINE_CHECK_HANDLER_WINDUP
b machine_check_pSeries
powerpc/book3s: Fix machine check handling for unhandled errors Current code does not check for unhandled/unrecovered errors and return from interrupt if it is recoverable exception which in-turn triggers same machine check exception in a loop causing hypervisor to be unresponsive. This patch fixes this situation and forces hypervisor to panic for unhandled/unrecovered errors. This patch also fixes another issue where unrecoverable_exception routine was called in real mode in case of unrecoverable exception (MSR_RI = 0). This causes another exception vector 0x300 (data access) during system crash leading to confusion while debugging cause of the system crash. Also turn ME bit off while going down, so that when another MCE is hit during panic path, system will checkstop and hypervisor will get restarted cleanly by SP. With the above fixes we now throw correct console messages (see below) while crashing the system in case of unhandled/unrecoverable machine checks. -------------- Severe Machine check interrupt [[Not recovered] Initiator: CPU Error type: UE [Instruction fetch] Effective address: 0000000030002864 Oops: Machine check, sig: 7 [#1] SMP NR_CPUS=2048 NUMA PowerNV Modules linked in: bork(O) bridge stp llc kvm [last unloaded: bork] CPU: 36 PID: 55162 Comm: bash Tainted: G O 3.14.0mce #1 task: c000002d72d022d0 ti: c000000007ec0000 task.ti: c000002d72de4000 NIP: 0000000030002864 LR: 00000000300151a4 CTR: 000000003001518c REGS: c000000007ec3d80 TRAP: 0200 Tainted: G O (3.14.0mce) MSR: 9000000000041002 <SF,HV,ME,RI> CR: 28222848 XER: 20000000 CFAR: 0000000030002838 DAR: d0000000004d0000 DSISR: 00000000 SOFTE: 1 GPR00: 000000003001512c 0000000031f92cb0 0000000030078af0 0000000030002864 GPR04: d0000000004d0000 0000000000000000 0000000030002864 ffffffffffffffc9 GPR08: 0000000000000024 0000000030008af0 000000000000002c c00000000150e728 GPR12: 9000000000041002 0000000031f90000 0000000010142550 0000000040000000 GPR16: 0000000010143cdc 0000000000000000 00000000101306fc 00000000101424dc GPR20: 00000000101424e0 000000001013c6f0 0000000000000000 0000000000000000 GPR24: 0000000010143ce0 00000000100f6440 c000002d72de7e00 c000002d72860250 GPR28: c000002d72860240 c000002d72ac0038 0000000000000008 0000000000040000 NIP [0000000030002864] 0x30002864 LR [00000000300151a4] 0x300151a4 Call Trace: Instruction dump: XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX ---[ end trace 7285f0beac1e29d3 ]--- Sending IPI to other CPUs IPI complete OPAL V3 detected ! -------------- Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-06-11 16:47:56 +08:00
unrecover_mce:
/* Invoke machine_check_exception to print MCE event and panic. */
addi r3,r1,STACK_FRAME_OVERHEAD
bl machine_check_exception
powerpc/book3s: Fix machine check handling for unhandled errors Current code does not check for unhandled/unrecovered errors and return from interrupt if it is recoverable exception which in-turn triggers same machine check exception in a loop causing hypervisor to be unresponsive. This patch fixes this situation and forces hypervisor to panic for unhandled/unrecovered errors. This patch also fixes another issue where unrecoverable_exception routine was called in real mode in case of unrecoverable exception (MSR_RI = 0). This causes another exception vector 0x300 (data access) during system crash leading to confusion while debugging cause of the system crash. Also turn ME bit off while going down, so that when another MCE is hit during panic path, system will checkstop and hypervisor will get restarted cleanly by SP. With the above fixes we now throw correct console messages (see below) while crashing the system in case of unhandled/unrecoverable machine checks. -------------- Severe Machine check interrupt [[Not recovered] Initiator: CPU Error type: UE [Instruction fetch] Effective address: 0000000030002864 Oops: Machine check, sig: 7 [#1] SMP NR_CPUS=2048 NUMA PowerNV Modules linked in: bork(O) bridge stp llc kvm [last unloaded: bork] CPU: 36 PID: 55162 Comm: bash Tainted: G O 3.14.0mce #1 task: c000002d72d022d0 ti: c000000007ec0000 task.ti: c000002d72de4000 NIP: 0000000030002864 LR: 00000000300151a4 CTR: 000000003001518c REGS: c000000007ec3d80 TRAP: 0200 Tainted: G O (3.14.0mce) MSR: 9000000000041002 <SF,HV,ME,RI> CR: 28222848 XER: 20000000 CFAR: 0000000030002838 DAR: d0000000004d0000 DSISR: 00000000 SOFTE: 1 GPR00: 000000003001512c 0000000031f92cb0 0000000030078af0 0000000030002864 GPR04: d0000000004d0000 0000000000000000 0000000030002864 ffffffffffffffc9 GPR08: 0000000000000024 0000000030008af0 000000000000002c c00000000150e728 GPR12: 9000000000041002 0000000031f90000 0000000010142550 0000000040000000 GPR16: 0000000010143cdc 0000000000000000 00000000101306fc 00000000101424dc GPR20: 00000000101424e0 000000001013c6f0 0000000000000000 0000000000000000 GPR24: 0000000010143ce0 00000000100f6440 c000002d72de7e00 c000002d72860250 GPR28: c000002d72860240 c000002d72ac0038 0000000000000008 0000000000040000 NIP [0000000030002864] 0x30002864 LR [00000000300151a4] 0x300151a4 Call Trace: Instruction dump: XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX ---[ end trace 7285f0beac1e29d3 ]--- Sending IPI to other CPUs IPI complete OPAL V3 detected ! -------------- Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-06-11 16:47:56 +08:00
/*
* We will not reach here. Even if we did, there is no way out. Call
* unrecoverable_exception and die.
*/
1: addi r3,r1,STACK_FRAME_OVERHEAD
bl unrecoverable_exception
powerpc/book3s: Fix machine check handling for unhandled errors Current code does not check for unhandled/unrecovered errors and return from interrupt if it is recoverable exception which in-turn triggers same machine check exception in a loop causing hypervisor to be unresponsive. This patch fixes this situation and forces hypervisor to panic for unhandled/unrecovered errors. This patch also fixes another issue where unrecoverable_exception routine was called in real mode in case of unrecoverable exception (MSR_RI = 0). This causes another exception vector 0x300 (data access) during system crash leading to confusion while debugging cause of the system crash. Also turn ME bit off while going down, so that when another MCE is hit during panic path, system will checkstop and hypervisor will get restarted cleanly by SP. With the above fixes we now throw correct console messages (see below) while crashing the system in case of unhandled/unrecoverable machine checks. -------------- Severe Machine check interrupt [[Not recovered] Initiator: CPU Error type: UE [Instruction fetch] Effective address: 0000000030002864 Oops: Machine check, sig: 7 [#1] SMP NR_CPUS=2048 NUMA PowerNV Modules linked in: bork(O) bridge stp llc kvm [last unloaded: bork] CPU: 36 PID: 55162 Comm: bash Tainted: G O 3.14.0mce #1 task: c000002d72d022d0 ti: c000000007ec0000 task.ti: c000002d72de4000 NIP: 0000000030002864 LR: 00000000300151a4 CTR: 000000003001518c REGS: c000000007ec3d80 TRAP: 0200 Tainted: G O (3.14.0mce) MSR: 9000000000041002 <SF,HV,ME,RI> CR: 28222848 XER: 20000000 CFAR: 0000000030002838 DAR: d0000000004d0000 DSISR: 00000000 SOFTE: 1 GPR00: 000000003001512c 0000000031f92cb0 0000000030078af0 0000000030002864 GPR04: d0000000004d0000 0000000000000000 0000000030002864 ffffffffffffffc9 GPR08: 0000000000000024 0000000030008af0 000000000000002c c00000000150e728 GPR12: 9000000000041002 0000000031f90000 0000000010142550 0000000040000000 GPR16: 0000000010143cdc 0000000000000000 00000000101306fc 00000000101424dc GPR20: 00000000101424e0 000000001013c6f0 0000000000000000 0000000000000000 GPR24: 0000000010143ce0 00000000100f6440 c000002d72de7e00 c000002d72860250 GPR28: c000002d72860240 c000002d72ac0038 0000000000000008 0000000000040000 NIP [0000000030002864] 0x30002864 LR [00000000300151a4] 0x300151a4 Call Trace: Instruction dump: XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX ---[ end trace 7285f0beac1e29d3 ]--- Sending IPI to other CPUs IPI complete OPAL V3 detected ! -------------- Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-06-11 16:47:56 +08:00
b 1b
/*
* r13 points to the PACA, r9 contains the saved CR,
* r12 contain the saved SRR1, SRR0 is still ready for return
* r3 has the faulting address
* r9 - r13 are saved in paca->exslb.
* r3 is saved in paca->slb_r3
* We assume we aren't going to take any exceptions during this procedure.
*/
slb_miss_realmode:
mflr r10
#ifdef CONFIG_RELOCATABLE
mtctr r11
#endif
stw r9,PACA_EXSLB+EX_CCR(r13) /* save CR in exc. frame */
std r10,PACA_EXSLB+EX_LR(r13) /* save LR */
bl slb_allocate_realmode
/* All done -- return from exception. */
ld r10,PACA_EXSLB+EX_LR(r13)
ld r3,PACA_EXSLB+EX_R3(r13)
lwz r9,PACA_EXSLB+EX_CCR(r13) /* get saved CR */
mtlr r10
andi. r10,r12,MSR_RI /* check for unrecoverable exception */
beq- 2f
.machine push
.machine "power4"
mtcrf 0x80,r9
mtcrf 0x01,r9 /* slb_allocate uses cr0 and cr7 */
.machine pop
RESTORE_PPR_PACA(PACA_EXSLB, r9)
ld r9,PACA_EXSLB+EX_R9(r13)
ld r10,PACA_EXSLB+EX_R10(r13)
ld r11,PACA_EXSLB+EX_R11(r13)
ld r12,PACA_EXSLB+EX_R12(r13)
ld r13,PACA_EXSLB+EX_R13(r13)
rfid
b . /* prevent speculative execution */
2: mfspr r11,SPRN_SRR0
ld r10,PACAKBASE(r13)
LOAD_HANDLER(r10,unrecov_slb)
mtspr SPRN_SRR0,r10
ld r10,PACAKMSR(r13)
mtspr SPRN_SRR1,r10
rfid
b .
unrecov_slb:
EXCEPTION_PROLOG_COMMON(0x4100, PACA_EXSLB)
RECONCILE_IRQ_STATE(r10, r11)
bl save_nvgprs
1: addi r3,r1,STACK_FRAME_OVERHEAD
bl unrecoverable_exception
b 1b
#ifdef CONFIG_PPC_970_NAP
power4_fixup_nap:
andc r9,r9,r10
std r9,TI_LOCAL_FLAGS(r11)
ld r10,_LINK(r1) /* make idle task do the */
std r10,_NIP(r1) /* equivalent of a blr */
blr
#endif
/*
* Hash table stuff
*/
.align 7
do_hash_page:
std r3,_DAR(r1)
std r4,_DSISR(r1)
andis. r0,r4,0xa410 /* weird error? */
bne- handle_page_fault /* if not, try to insert a HPTE */
andis. r0,r4,DSISR_DABRMATCH@h
bne- handle_dabr_fault
CURRENT_THREAD_INFO(r11, r1)
powerpc: Allow perf_counters to access user memory at interrupt time This provides a mechanism to allow the perf_counters code to access user memory in a PMU interrupt routine. Such an access can cause various kinds of interrupt: SLB miss, MMU hash table miss, segment table miss, or TLB miss, depending on the processor. This commit only deals with 64-bit classic/server processors, which use an MMU hash table. 32-bit processors are already able to access user memory at interrupt time. Since we don't soft-disable on 32-bit, we avoid the possibility of reentering hash_page or the TLB miss handlers, since they run with interrupts disabled. On 64-bit processors, an SLB miss interrupt on a user address will update the slb_cache and slb_cache_ptr fields in the paca. This is OK except in the case where a PMU interrupt occurs in switch_slb, which also accesses those fields. To prevent this, we hard-disable interrupts in switch_slb. Interrupts are already soft-disabled at this point, and will get hard-enabled when they get soft-enabled later. This also reworks slb_flush_and_rebolt: to avoid hard-disabling twice, and to make sure that it clears the slb_cache_ptr when called from other callers than switch_slb, the existing routine is renamed to __slb_flush_and_rebolt, which is called by switch_slb and the new version of slb_flush_and_rebolt. Similarly, switch_stab (used on POWER3 and RS64 processors) gets a hard_irq_disable() to protect the per-cpu variables used there and in ste_allocate. If a MMU hashtable miss interrupt occurs, normally we would call hash_page to look up the Linux PTE for the address and create a HPTE. However, hash_page is fairly complex and takes some locks, so to avoid the possibility of deadlock, we check the preemption count to see if we are in a (pseudo-)NMI handler, and if so, we don't call hash_page but instead treat it like a bad access that will get reported up through the exception table mechanism. An interrupt whose handler runs even though the interrupt occurred when soft-disabled (such as the PMU interrupt) is considered a pseudo-NMI handler, which should use nmi_enter()/nmi_exit() rather than irq_enter()/irq_exit(). Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2009-08-17 13:17:54 +08:00
lwz r0,TI_PREEMPT(r11) /* If we're in an "NMI" */
andis. r0,r0,NMI_MASK@h /* (i.e. an irq when soft-disabled) */
bne 77f /* then don't call hash_page now */
/*
* We need to set the _PAGE_USER bit if MSR_PR is set or if we are
* accessing a userspace segment (even from the kernel). We assume
* kernel addresses always have the high bit set.
*/
rlwinm r4,r4,32-25+9,31-9,31-9 /* DSISR_STORE -> _PAGE_RW */
rotldi r0,r3,15 /* Move high bit into MSR_PR posn */
orc r0,r12,r0 /* MSR_PR | ~high_bit */
rlwimi r4,r0,32-13,30,30 /* becomes _PAGE_USER access bit */
ori r4,r4,1 /* add _PAGE_PRESENT */
rlwimi r4,r5,22+2,31-2,31-2 /* Set _PAGE_EXEC if trap is 0x400 */
/*
* r3 contains the faulting address
* r4 contains the required access permissions
* r5 contains the trap number
*
powerpc: Rework lazy-interrupt handling The current implementation of lazy interrupts handling has some issues that this tries to address. We don't do the various workarounds we need to do when re-enabling interrupts in some cases such as when returning from an interrupt and thus we may still lose or get delayed decrementer or doorbell interrupts. The current scheme also makes it much harder to handle the external "edge" interrupts provided by some BookE processors when using the EPR facility (External Proxy) and the Freescale Hypervisor. Additionally, we tend to keep interrupts hard disabled in a number of cases, such as decrementer interrupts, external interrupts, or when a masked decrementer interrupt is pending. This is sub-optimal. This is an attempt at fixing it all in one go by reworking the way we do the lazy interrupt disabling from the ground up. The base idea is to replace the "hard_enabled" field with a "irq_happened" field in which we store a bit mask of what interrupt occurred while soft-disabled. When re-enabling, either via arch_local_irq_restore() or when returning from an interrupt, we can now decide what to do by testing bits in that field. We then implement replaying of the missed interrupts either by re-using the existing exception frame (in exception exit case) or via the creation of a new one from an assembly trampoline (in the arch_local_irq_enable case). This removes the need to play with the decrementer to try to create fake interrupts, among others. In addition, this adds a few refinements: - We no longer hard disable decrementer interrupts that occur while soft-disabled. We now simply bump the decrementer back to max (on BookS) or leave it stopped (on BookE) and continue with hard interrupts enabled, which means that we'll potentially get better sample quality from performance monitor interrupts. - Timer, decrementer and doorbell interrupts now hard-enable shortly after removing the source of the interrupt, which means they no longer run entirely hard disabled. Again, this will improve perf sample quality. - On Book3E 64-bit, we now make the performance monitor interrupt act as an NMI like Book3S (the necessary C code for that to work appear to already be present in the FSL perf code, notably calling nmi_enter instead of irq_enter). (This also fixes a bug where BookE perfmon interrupts could clobber r14 ... oops) - We could make "masked" decrementer interrupts act as NMIs when doing timer-based perf sampling to improve the sample quality. Signed-off-by-yet: Benjamin Herrenschmidt <benh@kernel.crashing.org> --- v2: - Add hard-enable to decrementer, timer and doorbells - Fix CR clobber in masked irq handling on BookE - Make embedded perf interrupt act as an NMI - Add a PACA_HAPPENED_EE_EDGE for use by FSL if they want to retrigger an interrupt without preventing hard-enable v3: - Fix or vs. ori bug on Book3E - Fix enabling of interrupts for some exceptions on Book3E v4: - Fix resend of doorbells on return from interrupt on Book3E v5: - Rebased on top of my latest series, which involves some significant rework of some aspects of the patch. v6: - 32-bit compile fix - more compile fixes with various .config combos - factor out the asm code to soft-disable interrupts - remove the C wrapper around preempt_schedule_irq v7: - Fix a bug with hard irq state tracking on native power7
2012-03-06 15:27:59 +08:00
* at return r3 = 0 for success, 1 for page fault, negative for error
*/
bl hash_page /* build HPTE if possible */
cmpdi r3,0 /* see if hash_page succeeded */
powerpc: Rework lazy-interrupt handling The current implementation of lazy interrupts handling has some issues that this tries to address. We don't do the various workarounds we need to do when re-enabling interrupts in some cases such as when returning from an interrupt and thus we may still lose or get delayed decrementer or doorbell interrupts. The current scheme also makes it much harder to handle the external "edge" interrupts provided by some BookE processors when using the EPR facility (External Proxy) and the Freescale Hypervisor. Additionally, we tend to keep interrupts hard disabled in a number of cases, such as decrementer interrupts, external interrupts, or when a masked decrementer interrupt is pending. This is sub-optimal. This is an attempt at fixing it all in one go by reworking the way we do the lazy interrupt disabling from the ground up. The base idea is to replace the "hard_enabled" field with a "irq_happened" field in which we store a bit mask of what interrupt occurred while soft-disabled. When re-enabling, either via arch_local_irq_restore() or when returning from an interrupt, we can now decide what to do by testing bits in that field. We then implement replaying of the missed interrupts either by re-using the existing exception frame (in exception exit case) or via the creation of a new one from an assembly trampoline (in the arch_local_irq_enable case). This removes the need to play with the decrementer to try to create fake interrupts, among others. In addition, this adds a few refinements: - We no longer hard disable decrementer interrupts that occur while soft-disabled. We now simply bump the decrementer back to max (on BookS) or leave it stopped (on BookE) and continue with hard interrupts enabled, which means that we'll potentially get better sample quality from performance monitor interrupts. - Timer, decrementer and doorbell interrupts now hard-enable shortly after removing the source of the interrupt, which means they no longer run entirely hard disabled. Again, this will improve perf sample quality. - On Book3E 64-bit, we now make the performance monitor interrupt act as an NMI like Book3S (the necessary C code for that to work appear to already be present in the FSL perf code, notably calling nmi_enter instead of irq_enter). (This also fixes a bug where BookE perfmon interrupts could clobber r14 ... oops) - We could make "masked" decrementer interrupts act as NMIs when doing timer-based perf sampling to improve the sample quality. Signed-off-by-yet: Benjamin Herrenschmidt <benh@kernel.crashing.org> --- v2: - Add hard-enable to decrementer, timer and doorbells - Fix CR clobber in masked irq handling on BookE - Make embedded perf interrupt act as an NMI - Add a PACA_HAPPENED_EE_EDGE for use by FSL if they want to retrigger an interrupt without preventing hard-enable v3: - Fix or vs. ori bug on Book3E - Fix enabling of interrupts for some exceptions on Book3E v4: - Fix resend of doorbells on return from interrupt on Book3E v5: - Rebased on top of my latest series, which involves some significant rework of some aspects of the patch. v6: - 32-bit compile fix - more compile fixes with various .config combos - factor out the asm code to soft-disable interrupts - remove the C wrapper around preempt_schedule_irq v7: - Fix a bug with hard irq state tracking on native power7
2012-03-06 15:27:59 +08:00
/* Success */
beq fast_exc_return_irq /* Return from exception on success */
powerpc: Rework lazy-interrupt handling The current implementation of lazy interrupts handling has some issues that this tries to address. We don't do the various workarounds we need to do when re-enabling interrupts in some cases such as when returning from an interrupt and thus we may still lose or get delayed decrementer or doorbell interrupts. The current scheme also makes it much harder to handle the external "edge" interrupts provided by some BookE processors when using the EPR facility (External Proxy) and the Freescale Hypervisor. Additionally, we tend to keep interrupts hard disabled in a number of cases, such as decrementer interrupts, external interrupts, or when a masked decrementer interrupt is pending. This is sub-optimal. This is an attempt at fixing it all in one go by reworking the way we do the lazy interrupt disabling from the ground up. The base idea is to replace the "hard_enabled" field with a "irq_happened" field in which we store a bit mask of what interrupt occurred while soft-disabled. When re-enabling, either via arch_local_irq_restore() or when returning from an interrupt, we can now decide what to do by testing bits in that field. We then implement replaying of the missed interrupts either by re-using the existing exception frame (in exception exit case) or via the creation of a new one from an assembly trampoline (in the arch_local_irq_enable case). This removes the need to play with the decrementer to try to create fake interrupts, among others. In addition, this adds a few refinements: - We no longer hard disable decrementer interrupts that occur while soft-disabled. We now simply bump the decrementer back to max (on BookS) or leave it stopped (on BookE) and continue with hard interrupts enabled, which means that we'll potentially get better sample quality from performance monitor interrupts. - Timer, decrementer and doorbell interrupts now hard-enable shortly after removing the source of the interrupt, which means they no longer run entirely hard disabled. Again, this will improve perf sample quality. - On Book3E 64-bit, we now make the performance monitor interrupt act as an NMI like Book3S (the necessary C code for that to work appear to already be present in the FSL perf code, notably calling nmi_enter instead of irq_enter). (This also fixes a bug where BookE perfmon interrupts could clobber r14 ... oops) - We could make "masked" decrementer interrupts act as NMIs when doing timer-based perf sampling to improve the sample quality. Signed-off-by-yet: Benjamin Herrenschmidt <benh@kernel.crashing.org> --- v2: - Add hard-enable to decrementer, timer and doorbells - Fix CR clobber in masked irq handling on BookE - Make embedded perf interrupt act as an NMI - Add a PACA_HAPPENED_EE_EDGE for use by FSL if they want to retrigger an interrupt without preventing hard-enable v3: - Fix or vs. ori bug on Book3E - Fix enabling of interrupts for some exceptions on Book3E v4: - Fix resend of doorbells on return from interrupt on Book3E v5: - Rebased on top of my latest series, which involves some significant rework of some aspects of the patch. v6: - 32-bit compile fix - more compile fixes with various .config combos - factor out the asm code to soft-disable interrupts - remove the C wrapper around preempt_schedule_irq v7: - Fix a bug with hard irq state tracking on native power7
2012-03-06 15:27:59 +08:00
/* Error */
blt- 13f
/* Here we have a page fault that hash_page can't handle. */
handle_page_fault:
11: ld r4,_DAR(r1)
ld r5,_DSISR(r1)
addi r3,r1,STACK_FRAME_OVERHEAD
bl do_page_fault
cmpdi r3,0
beq+ 12f
bl save_nvgprs
mr r5,r3
addi r3,r1,STACK_FRAME_OVERHEAD
lwz r4,_DAR(r1)
bl bad_page_fault
b ret_from_except
/* We have a data breakpoint exception - handle it */
handle_dabr_fault:
bl save_nvgprs
ld r4,_DAR(r1)
ld r5,_DSISR(r1)
addi r3,r1,STACK_FRAME_OVERHEAD
bl do_break
12: b ret_from_except_lite
/* We have a page fault that hash_page could handle but HV refused
* the PTE insertion
*/
13: bl save_nvgprs
mr r5,r3
addi r3,r1,STACK_FRAME_OVERHEAD
ld r4,_DAR(r1)
bl low_hash_fault
b ret_from_except
powerpc: Allow perf_counters to access user memory at interrupt time This provides a mechanism to allow the perf_counters code to access user memory in a PMU interrupt routine. Such an access can cause various kinds of interrupt: SLB miss, MMU hash table miss, segment table miss, or TLB miss, depending on the processor. This commit only deals with 64-bit classic/server processors, which use an MMU hash table. 32-bit processors are already able to access user memory at interrupt time. Since we don't soft-disable on 32-bit, we avoid the possibility of reentering hash_page or the TLB miss handlers, since they run with interrupts disabled. On 64-bit processors, an SLB miss interrupt on a user address will update the slb_cache and slb_cache_ptr fields in the paca. This is OK except in the case where a PMU interrupt occurs in switch_slb, which also accesses those fields. To prevent this, we hard-disable interrupts in switch_slb. Interrupts are already soft-disabled at this point, and will get hard-enabled when they get soft-enabled later. This also reworks slb_flush_and_rebolt: to avoid hard-disabling twice, and to make sure that it clears the slb_cache_ptr when called from other callers than switch_slb, the existing routine is renamed to __slb_flush_and_rebolt, which is called by switch_slb and the new version of slb_flush_and_rebolt. Similarly, switch_stab (used on POWER3 and RS64 processors) gets a hard_irq_disable() to protect the per-cpu variables used there and in ste_allocate. If a MMU hashtable miss interrupt occurs, normally we would call hash_page to look up the Linux PTE for the address and create a HPTE. However, hash_page is fairly complex and takes some locks, so to avoid the possibility of deadlock, we check the preemption count to see if we are in a (pseudo-)NMI handler, and if so, we don't call hash_page but instead treat it like a bad access that will get reported up through the exception table mechanism. An interrupt whose handler runs even though the interrupt occurred when soft-disabled (such as the PMU interrupt) is considered a pseudo-NMI handler, which should use nmi_enter()/nmi_exit() rather than irq_enter()/irq_exit(). Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2009-08-17 13:17:54 +08:00
/*
* We come here as a result of a DSI at a point where we don't want
* to call hash_page, such as when we are accessing memory (possibly
* user memory) inside a PMU interrupt that occurred while interrupts
* were soft-disabled. We want to invoke the exception handler for
* the access, or panic if there isn't a handler.
*/
77: bl save_nvgprs
powerpc: Allow perf_counters to access user memory at interrupt time This provides a mechanism to allow the perf_counters code to access user memory in a PMU interrupt routine. Such an access can cause various kinds of interrupt: SLB miss, MMU hash table miss, segment table miss, or TLB miss, depending on the processor. This commit only deals with 64-bit classic/server processors, which use an MMU hash table. 32-bit processors are already able to access user memory at interrupt time. Since we don't soft-disable on 32-bit, we avoid the possibility of reentering hash_page or the TLB miss handlers, since they run with interrupts disabled. On 64-bit processors, an SLB miss interrupt on a user address will update the slb_cache and slb_cache_ptr fields in the paca. This is OK except in the case where a PMU interrupt occurs in switch_slb, which also accesses those fields. To prevent this, we hard-disable interrupts in switch_slb. Interrupts are already soft-disabled at this point, and will get hard-enabled when they get soft-enabled later. This also reworks slb_flush_and_rebolt: to avoid hard-disabling twice, and to make sure that it clears the slb_cache_ptr when called from other callers than switch_slb, the existing routine is renamed to __slb_flush_and_rebolt, which is called by switch_slb and the new version of slb_flush_and_rebolt. Similarly, switch_stab (used on POWER3 and RS64 processors) gets a hard_irq_disable() to protect the per-cpu variables used there and in ste_allocate. If a MMU hashtable miss interrupt occurs, normally we would call hash_page to look up the Linux PTE for the address and create a HPTE. However, hash_page is fairly complex and takes some locks, so to avoid the possibility of deadlock, we check the preemption count to see if we are in a (pseudo-)NMI handler, and if so, we don't call hash_page but instead treat it like a bad access that will get reported up through the exception table mechanism. An interrupt whose handler runs even though the interrupt occurred when soft-disabled (such as the PMU interrupt) is considered a pseudo-NMI handler, which should use nmi_enter()/nmi_exit() rather than irq_enter()/irq_exit(). Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2009-08-17 13:17:54 +08:00
mr r4,r3
addi r3,r1,STACK_FRAME_OVERHEAD
li r5,SIGSEGV
bl bad_page_fault
b ret_from_except
/*
* Here we have detected that the kernel stack pointer is bad.
* R9 contains the saved CR, r13 points to the paca,
* r10 contains the (bad) kernel stack pointer,
* r11 and r12 contain the saved SRR0 and SRR1.
* We switch to using an emergency stack, save the registers there,
* and call kernel_bad_stack(), which panics.
*/
bad_stack:
ld r1,PACAEMERGSP(r13)
subi r1,r1,64+INT_FRAME_SIZE
std r9,_CCR(r1)
std r10,GPR1(r1)
std r11,_NIP(r1)
std r12,_MSR(r1)
mfspr r11,SPRN_DAR
mfspr r12,SPRN_DSISR
std r11,_DAR(r1)
std r12,_DSISR(r1)
mflr r10
mfctr r11
mfxer r12
std r10,_LINK(r1)
std r11,_CTR(r1)
std r12,_XER(r1)
SAVE_GPR(0,r1)
SAVE_GPR(2,r1)
ld r10,EX_R3(r3)
std r10,GPR3(r1)
SAVE_GPR(4,r1)
SAVE_4GPRS(5,r1)
ld r9,EX_R9(r3)
ld r10,EX_R10(r3)
SAVE_2GPRS(9,r1)
ld r9,EX_R11(r3)
ld r10,EX_R12(r3)
ld r11,EX_R13(r3)
std r9,GPR11(r1)
std r10,GPR12(r1)
std r11,GPR13(r1)
BEGIN_FTR_SECTION
ld r10,EX_CFAR(r3)
std r10,ORIG_GPR3(r1)
END_FTR_SECTION_IFSET(CPU_FTR_CFAR)
SAVE_8GPRS(14,r1)
SAVE_10GPRS(22,r1)
lhz r12,PACA_TRAP_SAVE(r13)
std r12,_TRAP(r1)
addi r11,r1,INT_FRAME_SIZE
std r11,0(r1)
li r12,0
std r12,0(r11)
ld r2,PACATOC(r13)
ld r11,exception_marker@toc(r2)
std r12,RESULT(r1)
std r11,STACK_FRAME_OVERHEAD-16(r1)
1: addi r3,r1,STACK_FRAME_OVERHEAD
bl kernel_bad_stack
b 1b