Commit Graph

17554 Commits

Author SHA1 Message Date
Ram Pai 013a91b39c powerpc: ability to associate pkey to a vma
arch-independent code expects the arch to  map
a  pkey  into the vma's protection bit setting.
The patch provides that ability.

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-20 22:59:01 +11:00
Ram Pai 5586cf61e1 powerpc: introduce execute-only pkey
This patch provides the implementation of execute-only pkey.
The architecture-independent layer expects the arch-dependent
layer, to support the ability to create and enable a special
key which has execute-only permission.

Acked-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-20 22:59:01 +11:00
Ram Pai 06bb53b338 powerpc: store and restore the pkey state across context switches
Store and restore the AMR, IAMR and UAMOR register state of the task
before scheduling out and after scheduling in, respectively.

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-20 22:59:00 +11:00
Ram Pai dcf872956d powerpc: ability to create execute-disabled pkeys
powerpc has hardware support to disable execute on a pkey.
This patch enables the ability to create execute-disabled
keys.

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-20 22:59:00 +11:00
Ram Pai 2ddc53f3a7 powerpc: implementation for arch_set_user_pkey_access()
This patch provides the detailed implementation for
a user to allocate a key and enable it in the hardware.

It provides the plumbing, but it cannot be used till
the system call is implemented. The next patch  will
do so.

Reviewed-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-20 22:58:59 +11:00
Ram Pai 0685f217af powerpc: cleanup AMR, IAMR when a key is allocated or freed
Cleanup the bits corresponding to a key in the AMR, and IAMR
register, when the key is newly allocated/activated or is freed.
We dont want some residual bits cause the hardware enforce
unintended behavior when the key is activated or freed.

Reviewed-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-20 22:58:59 +11:00
Ram Pai 4d70b698f9 powerpc: helper functions to initialize AMR, IAMR and UAMOR registers
Introduce  helper functions that can initialize the bits in the AMR,
IAMR and UAMOR register; the bits that correspond to the given pkey.

Reviewed-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-20 22:58:58 +11:00
Ram Pai 1b4037dead powerpc: helper function to read, write AMR, IAMR, UAMOR registers
Implements helper functions to read and write the key related
registers; AMR, IAMR, UAMOR.

AMR register tracks the read,write permission of a key
IAMR register tracks the execute permission of a key
UAMOR register enables and disables a key

Acked-by: Balbir Singh <bsingharora@gmail.com>
Reviewed-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-20 22:58:58 +11:00
Ram Pai 4fb158f65a powerpc: track allocation status of all pkeys
Total 32 keys are available on power7 and above. However
pkey 0,1 are reserved. So effectively we  have  30 pkeys.

On 4K kernels, we do not  have  5  bits  in  the  PTE to
represent  all the keys; we only have 3bits. Two of those
keys are reserved; pkey 0 and pkey 1. So effectively  we
have 6 pkeys.

This patch keeps track of reserved keys, allocated  keys
and keys that are currently free.

Also it  adds  skeletal  functions  and macros, that the
architecture-independent code expects to be available.

Reviewed-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-20 22:58:35 +11:00
Ram Pai 92e3da3cf1 powerpc: initial pkey plumbing
Basic  plumbing  to   initialize  the   pkey  system.
Nothing is enabled yet. A later patch will enable it
once all the infrastructure is in place.

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
[mpe: Rework copyrights to use SPDX tags]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-20 21:45:03 +11:00
Christophe Lombard b1db551324 cxl: Add support for ASB_Notify on POWER9
The POWER9 core supports a new feature: ASB_Notify which requires the
support of the Special Purpose Register: TIDR.

The ASB_Notify command, generated by the AFU, will attempt to
wake-up the host thread identified by the particular LPID:PID:TID.

This patch assign a unique TIDR (thread id) for the current thread which
will be used in the process element entry.

Signed-off-by: Christophe Lombard <clombard@linux.vnet.ibm.com>
Reviewed-by: Philippe Bergheaud <felix@linux.vnet.ibm.com>
Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Reviewed-by: Vaibhav Jain <vaibhav@linux.vnet.ibm.com>
Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-19 23:19:37 +11:00
Anju T Sudhakar 074db39e00 powerpc/perf: Change the data type for the variable 'ncpu' in IMC code
Change the data type for the variable 'ncpu' in ppc_core_imc_cpu_offline(),
since cpumask_any_but() returns an 'int' value.

Signed-off-by: Anju T Sudhakar <anju@linux.vnet.ibm.com>
Reported-by: David Binderman <dcb314@hotmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-19 23:05:01 +11:00
Anju T Sudhakar 684d984038 powerpc/powernv: Add debugfs interface for imc-mode and imc-command
In memory Collection (IMC) counter pmu driver controls the ucode's
execution state. At the system boot, IMC perf driver pause the ucode.
Ucode state is changed to "running" only when any of the nest units
are monitored or profiled using perf tool.

Nest units support only limited set of hardware counters and ucode is
always programmed in the "production mode" ("accumulation") mode. This
mode is configured to provide key performance metric data for most of
the nest units.

But ucode also supports other modes which would be used for "debug" to
drill down specific nest units. That is, ucode when switched to
"powerbus" debug mode (for example), will dynamically reconfigure the
nest counters to target only "powerbus" related events in the hardware
counters. This allows the IMC nest unit to focus on powerbus related
transactions in the system in more detail. At this point, production
mode events may or may not be counted.

IMC nest counters has both in-band (ucode access) and out of band
access to it. Since not all nest counter configurations are supported
by ucode, out of band tools are used to characterize other nest
counter configurations.

Patch provides an interface via "debugfs" to enable the switching of
ucode modes in the system. To switch ucode mode, one has to first
pause the microcode (imc_cmd), and then write the target mode value to
the "imc_mode" file.

Proposed Approach:

In the proposed approach, the function (export_imc_mode_and_cmd) which
creates the debugfs interface for imc mode and command is implemented
in opal-imc.c. Thus we can use imc_get_mem_addr() to get the homer
base address for each chip.

The interface to expose imc mode and command is required only if we
have nest pmu units registered. Employing the existing data structures
to track whether we have any nest units registered will require to
extend data from perf side to opal-imc.c. Instead an integer is
introduced to hold that information by counting successful nest unit
registration. Debugfs interface is removed based on the integer count.

Example for the interface:

  $ ls /sys/kernel/debug/imc
  imc_cmd_0  imc_cmd_8  imc_mode_0  imc_mode_8

Signed-off-by: Anju T Sudhakar <anju@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-19 23:05:00 +11:00
Anju T Sudhakar 8b4e6deaff powerpc/perf: Pass struct imc_events as a parameter to imc_parse_event()
Remove the allocation of struct imc_events from imc_parse_event().
Instead pass imc_events as a parameter to imc_parse_event(), which is
a pointer to a slot in the array allocated in
update_events_in_group().

Reported-by: Dan Carpenter ("powerpc/perf: Fix a sizeof() typo so we allocate less memory")
Suggested-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Anju T Sudhakar <anju@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-19 23:04:44 +11:00
Anju T Sudhakar ed8e443fee powerpc/perf: IMC code cleanup with some code refactoring
Factor out memory freeing part for attribute elements from
imc_common_cpuhp_mem_free().

Signed-off-by: Anju T Sudhakar <anju@linux.vnet.ibm.com>
Reviewed-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-19 22:43:18 +11:00
Anju T Sudhakar e7673818d9 powerpc/perf: Remove thread_imc_pmu global variable from
Remove the global variable 'thread_imc_pmu', since it is not used in the code.

Signed-off-by: Anju T Sudhakar <anju@linux.vnet.ibm.com>
Reviewed-by: madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-19 22:39:57 +11:00
Madhavan Srinivasan 6cd74d2b61 powerpc/64s: Implement local_t using irq soft masking
local_t is used for atomic modifications for per-CPU data, versus
re-entrant modifications via interrupts.

local_t read-modify-write atomic operations are currently implemented
with hardware atomics (larx/stcx), which are quite slow. This patch
implements them by masking all types of interrupts that may do local_t
operations ("standard" and perf interrupts).

Rusty's benchmark (https://lkml.org/lkml/2008/12/16/450) gives the
following timings for the local_t test, in nanoseconds per iteration:

             larx/stcx   irq+pmu disable
_inc                38                10
_add                38                10
_read                4                 4
_add_return         38                10

There are still some interrupt types (system reset, machine check, and
watchdog), which can not safely use local_t operations, because they
are not masked.

An alternative approach was proposed, using a CR bit to mark a critical
section, which is tested in the interrupt return path, and would then
branch to a fixup handler (similar to exception fixups), which re-starts
the operation. The problem with this was the complexity of the fixup
handler and the latency of the slow path.

https://lists.ozlabs.org/pipermail/linuxppc-dev/2014-November/123024.html

Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-19 22:37:04 +11:00
Madhavan Srinivasan 3b7e302086 powerpc: use generic atomic implementation for local_t
powerpc implements local_t with atomic operations. There is already
an asm-generic implementation which does this using atomic_t.

Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-19 22:37:04 +11:00
Madhavan Srinivasan c6424382de powerpc/64s: Add new set of irq_soft_mask_ functions for PMI masking
To support soft-masking of the performance monitor interrupt, a set of
new powerpc_local_irq_pmu_save() and powerpc_local_irq_restore()
functions are added. And powerpc_local_irq_save() implemented, by
adding a new irq_soft_mask manipulation function
irq_soft_mask_or_return().

Local_irq_pmu_* macros are provided to access these
powerpc_local_irq_pmu* functions which includes
trace_hardirqs_on|off() to match what we have in
include/linux/irqflags.h.

Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-19 22:37:03 +11:00
Madhavan Srinivasan 9aa88188ee powerpc: Add new kconfig CONFIG_PPC_IRQ_SOFT_MASK_DEBUG
New Kconfig is added "CONFIG_PPC_IRQ_SOFT_MASK_DEBUG" to add WARN_ON
to alert the invalid transitions. Also moved the code under the
CONFIG_TRACE_IRQFLAGS in arch_local_irq_restore() to new Kconfig.

Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
[mpe: Fix name of CONFIG option in change log]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-19 22:37:03 +11:00
Madhavan Srinivasan f442d00480 powerpc/64s: Add support to mask perf interrupts and replay them
Two new bit mask field "IRQ_DISABLE_MASK_PMU" is introduced to support
the masking of PMI and "IRQ_DISABLE_MASK_ALL" to aid interrupt masking
checking.

Couple of new irq #defs "PACA_IRQ_PMI" and "SOFTEN_VALUE_0xf0*" added
to use in the exception code to check for PMI interrupts.

In the masked_interrupt handler, for PMIs we reset the MSR[EE] and
return. In the __check_irq_replay(), replay the PMI interrupt by
calling performance_monitor_common handler.

Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-19 22:37:02 +11:00
Madhavan Srinivasan f14e953b19 powerpc/64s: Add support to take additional parameter in MASKABLE_* macro
To support addition of "bitmask" to MASKABLE_* macros, factor out the
EXCPETION_PROLOG_1 macro.

Make it explicit the interrupt masking supported by a gievn interrupt
handler. Patch correspondingly extends the MASKABLE_* macros with an
addition's parameter. "bitmask" parameter is passed to SOFTEN_TEST
macro to decide on masking the interrupt.

Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-19 22:37:02 +11:00
Madhavan Srinivasan d32eb1b550 powerpc/64s: Avoid using EXCEPTION_PROLOG_1 macro in MASKABLE_*
Currently we use both EXCEPTION_PROLOG_1 and __EXCEPTION_PROLOG_1 in
the MASKABLE_* macros. As a cleanup, this patch makes MASKABLE_* to
use only __EXCEPTION_PROLOG_1. There is not logic change.

Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-19 22:37:01 +11:00
Madhavan Srinivasan 4e26bc4a4e powerpc/64: Rename soft_enabled to irq_soft_mask
Rename the paca->soft_enabled to paca->irq_soft_mask as it is no
longer used as a flag for interrupt state, but a mask.

Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-19 22:37:01 +11:00
Madhavan Srinivasan 01417c6cc7 powerpc/64: Change soft_enabled from flag to bitmask
"paca->soft_enabled" is used as a flag to mask some of interrupts.
Currently supported flags values and their details:

soft_enabled    MSR[EE]

0               0       Disabled (PMI and HMI not masked)
1               1       Enabled

"paca->soft_enabled" is initialized to 1 to make the interripts as
enabled. arch_local_irq_disable() will toggle the value when
interrupts needs to disbled. At this point, the interrupts are not
actually disabled, instead, interrupt vector has code to check for the
flag and mask it when it occurs. By "mask it", it update interrupt
paca->irq_happened and return. arch_local_irq_restore() is called to
re-enable interrupts, which checks and replays interrupts if any
occured.

Now, as mentioned, current logic doesnot mask "performance monitoring
interrupts" and PMIs are implemented as NMI. But this patchset depends
on local_irq_* for a successful local_* update. Meaning, mask all
possible interrupts during local_* update and replay them after the
update.

So the idea here is to reserve the "paca->soft_enabled" logic. New
values and details:

soft_enabled    MSR[EE]

1               0       Disabled  (PMI and HMI not masked)
0               1       Enabled

Reason for the this change is to create foundation for a third mask
value "0x2" for "soft_enabled" to add support to mask PMIs. When
->soft_enabled is set to a value "3", PMI interrupts are mask and when
set to a value of "1", PMI are not mask. With this patch also extends
soft_enabled as interrupt disable mask.

Current flags are renamed from IRQ_[EN?DIS}ABLED to
IRQS_ENABLED and IRQS_DISABLED.

Patch also fixes the ptrace call to force the user to see the softe
value to be alway 1. Reason being, even though userspace has no
business knowing about softe, it is part of pt_regs. Like-wise in
signal context.

Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-19 22:37:00 +11:00
Madhavan Srinivasan acb396d7c2 powerpc/64: Cleanup hard_irq_disable() macro
Minor cleanup to use helper function for manipulating
paca->soft_enabled variable.

Suggested-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-19 22:37:00 +11:00
Madhavan Srinivasan a67c543aac powerpc/64: Implement and use soft_enabled_set_return API
Add a new wrapper function, soft_enabled_set_return(), added to do the
paca->soft_enabled updates requiring a set-return.

Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-19 22:36:59 +11:00
Madhavan Srinivasan e0b5687bed powerpc/64: Implement and use soft_enabled_return API
Add a new wrapper function, soft_enabled_return(), added to return
paca->soft_enabled value.

Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-19 22:36:59 +11:00
Madhavan Srinivasan 0b63acf4a0 powerpc/64: Move set_soft_enabled() and rename
Move set_soft_enabled() from powerpc/kernel/irq.c to asm/hw_irq.c, to
encourage updates to paca->soft_enabled done via these access
function. Add "memory" clobber to hint compiler since
paca->soft_enabled memory is the target here.

Renaming it as soft_enabled_set() will make namespaces works better as
prefix than a postfix when new soft_enabled manipulation functions are
introduced.

Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-19 22:36:58 +11:00
Madhavan Srinivasan b5c1bd62c0 powerpc/64: Fix arch_local_irq_disable() prototype
In powerpc/64, the arch_local_irq_disable() function returns unsigned
long, which is not consistent with other architectures.

Move that set-return asm implementation into arch_local_irq_save(),
and make arch_local_irq_disable() return void, simplifying the
assembly.

Suggested-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-19 22:36:58 +11:00
Nicholas Piggin 9f83e00f4c powerpc/64: Improve inline asm in arch_local_irq_disable
arch_local_irq_disable is implemented strangely, with a temporary
output register being set to the desired soft_enabled value via an
immediate input, which is then used to store to memory. This is not
required, the immediate can be specified directly as a register input.

For simple cases at least, assembly is unchanged except register
mapping.

Reviewed-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-19 22:36:57 +11:00
Madhavan Srinivasan c2e480ba82 powerpc/64: Add #defines for paca->soft_enabled flags
Two #defines IRQS_ENABLED and IRQS_DISABLED are added to be used when
updating paca->soft_enabled. Replace the hardcoded values used when
updating paca->soft_enabled with IRQ_(EN|DIS)ABLED #define. No logic
change.

Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-19 22:36:56 +11:00
Madhavan Srinivasan a8a4b03ab9 powerpc: Hard wire PT_SOFTE value to 1 in ptrace & signals
We have always had softe in pt_regs, and accessible via PT_SOFTE, even
though it is not userspace state.

The value userspace sees should always be 1, because we should never
be in userspace with interrupts soft disabled.

In a subsequent patch we will be changing the semantics of the kernel
softe value, so hard wire the value to 1 to retain the existing
semantics. As far as we know nothing ever looks at it, but better safe
than sorry.

Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
[mpe: Split out of larger patch, write change log]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-19 22:36:54 +11:00
Michael Ellerman 7a074fc083 powerpc/64s: Fix ps3 build error due to tlbiel_all()
The recent changes to TLB handling broke the PS3 build:

  arch/powerpc/include/asm/book3s/64/tlbflush.h:30: undefined reference to `.hash__tlbiel_all'

Fix it by adding an fallback version of tlbiel_all() for non-native
builds. It should never be called, due to checks in callers so it
calls BUG(). We should probably clean it up further but this will
suffice for now.

Fixes: d4748276ae ("powerpc/64s: Improve local TLB flush for boot and MCE on POWER9")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-19 22:36:45 +11:00
Nicholas Piggin c16bee4bde powerpc: define __ARCH_IRQ_EXIT_IRQS_DISABLED
powerpc calls irq_exit() with local irqs disabled, therefore it
can define __ARCH_IRQ_EXIT_IRQS_DISABLED.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-18 15:43:43 +11:00
Nicholas Piggin 47712a921b powerpc/watchdog: remove arch_trigger_cpumask_backtrace
The powerpc NMI IPIs may not be recoverable if they are taken in
some sections of code, and also there have been and still are issues
with taking NMIs (in KVM guest code, in firmware, etc) which makes them
a bit dangerous to use.

Generic code like softlockup detector and rcu stall detectors really
hammer on trigger_*_backtrace, which has lead to further problems
because we've implemented it with the NMI.

So stop providing NMI backtraces for now. Importantly, the powerpc code
uses NMI IPIs in crash/debug, and the SMP hardlockup watchdog. So if the
softlockup and rcu hang detection traces are not being printed because
the CPU is stuck with interrupts off, then the hard lockup watchdog
should get it with the NMI IPI.

Fixes: 2104180a53 ("powerpc/64s: implement arch-specific hardlockup watchdog")
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-18 15:43:43 +11:00
Nicholas Piggin 1af19331a3 powerpc/64s: Relax PACA address limitations
Book3S PACA memory allocation is restricted by the RMA limit and also
must not take SLB faults when accessed in virtual mode. Currently a
fixed 256MB limit is used for this, which is imprecise and sub-optimal.

Update the paca allocation limits to use use the ppc64_rma_size for RMA
limit, and share the safe_stack_limit() that is currently used for stack
allocations that must not take virtual mode faults.

The safe_stack_limit() name is changed to ppc64_bolted_size() to match
ppc64_rma_size and some comments are updated. We also need to use
early_mmu_has_feature() because we are now calling this function prior
to the jump label patching that enables mmu_has_feature().

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Change mmu_has_feature() to early_mmu_has_feature()]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-18 15:42:48 +11:00
Nicholas Piggin c610d65c0a powerpc/pseries: lift RTAS limit for hash
With the previous patch to switch to 64-bit mode after returning from
RTAS and before doing any memory accesses, the RMA limit need not be
clamped to 1GB to avoid RTAS bugs.

Keep the 1GB limit for older firmware (although this is more of a kernel
concern than RTAS), and remove it starting with POWER9.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-18 00:45:34 +11:00
Nicholas Piggin 5eae82cab5 powerpc/pseries: lift RTAS limit for radix
With the previous patch to switch to 64-bit mode after returning from
RTAS and before doing any memory accesses, the RMA limit need not be
clamped to 1GB to avoid RTAS bugs.

Keep the 1GB limit for older firmware (although this is more of a kernel
concern than RTAS), and remove it starting with POWER9.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-18 00:44:42 +11:00
Nicholas Piggin 47fee31dbd powerpc/64: rtas avoid accessing paca in 32-bit mode
Commit 177ba7c647 ("powerpc/mm/radix: Limit paca allocation in radix")
limited the paca allocation address to 1G on pSeries because RTAS return
accesses the paca in 32-bit mode:

    On return from RTAS we access the paca variables and we have 64 bit
    disabled. This requires us to limit paca in 32 bit range.

    Fix this by setting ppc64_rma_size to first_memblock_size/1G range.

Avoid this limit by switching to 64-bit mode before accessing any memory.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-18 00:42:58 +11:00
Nicholas Piggin 98ae0069cb powerpc/pseries: radix is not subject to RMA limit, remove it
The radix guest is not subject to the paravirtualized HPT VRMA limit,
so remove that from ppc64_rma_size calculation for that platform.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-18 00:42:14 +11:00
Nicholas Piggin 1513c33d71 powerpc/powernv: Remove real mode access limit for early allocations
This removes the RMA limit on powernv platform, which constrains
early allocations such as PACAs and stacks. There are still other
restrictions that must be followed, such as bolted SLB limits, but
real mode addressing has no constraints.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-18 00:41:44 +11:00
Nicholas Piggin d4748276ae powerpc/64s: Improve local TLB flush for boot and MCE on POWER9
There are several cases outside the normal address space management
where a CPU's entire local TLB is to be flushed:

  1. Booting the kernel, in case something has left stale entries in
     the TLB (e.g., kexec).

  2. Machine check, to clean corrupted TLB entries.

One other place where the TLB is flushed, is waking from deep idle
states. The flush is a side-effect of calling ->cpu_restore with the
intention of re-setting various SPRs. The flush itself is unnecessary
because in the first case, the TLB should not acquire new corrupted
TLB entries as part of sleep/wake (though they may be lost).

This type of TLB flush is coded inflexibly, several times for each CPU
type, and they have a number of problems with ISA v3.0B:

- The current radix mode of the MMU is not taken into account, it is
  always done as a hash flushn For IS=2 (LPID-matching flush from host)
  and IS=3 with HV=0 (guest kernel flush), tlbie(l) is undefined if
  the R field does not match the current radix mode.

- ISA v3.0B hash must flush the partition and process table caches as
  well.

- ISA v3.0B radix must flush partition and process scoped translations,
  partition and process table caches, and also the page walk cache.

So consolidate the flushing code and implement it in C and inline asm
under the mm/ directory with the rest of the flush code. Add ISA v3.0B
cases for radix and hash, and use the radix flush in radix environment.

Provide a way for IS=2 (LPID flush) to specify the radix mode of the
partition. Have KVM pass in the radix mode of the guest.

Take out the flushes from early cputable/dt_cpu_ftrs detection hooks,
and move it later in the boot process after, the MMU registers are set
up and before relocation is first turned on.

The TLB flush is no longer called when restoring from deep idle states.
This was not be done as a separate step because booting secondaries
uses the same cpu_restore as idle restore, which needs the TLB flush.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-18 00:40:31 +11:00
Nicholas Piggin 4552d128c2 powerpc: System reset avoid interleaving oops using die synchronisation
The die() oops path contains a serializing lock to prevent oops
messages from being interleaved. In the case of a system reset
initiated oops (e.g., qemu nmi command), __die was being called
which lacks that synchronisation and oops reports could be
interleaved across CPUs.

A recent patch 4388c9b3a6 ("powerpc: Do not send system reset
request through the oops path") changed this to __die to avoid
the debugger() call, but there is no real harm to calling it twice
if the first time fell through. So go back to using die() here.
This was observed to fix the problem.

Fixes: 4388c9b3a6 ("powerpc: Do not send system reset request through the oops path")
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-18 00:38:59 +11:00
Benjamin Herrenschmidt 2271db20e4 powerpc: Use the TRAP macro whenever comparing a trap number
Trap numbers can have extra bits at the bottom that need to
be filtered out. There are a few cases where we don't do that.

It's possible that we got lucky but better safe than sorry.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-16 23:51:43 +11:00
Benjamin Herrenschmidt 872e2ae4bd powerpc: Remove useless EXC_COMMON_HV
The only difference between EXC_COMMON_HV and EXC_COMMON is that the
former adds "2" to the trap number which is supposed to represent the
fact that this is an "HV" interrupt which uses HSRR0/1.

However KVM is the only one who cares and it has its own separate macros.

In fact, we only have one user of EXC_COMMON_HV and it's for an
unknown interrupt case. All the other ones already using EXC_COMMON.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-16 23:51:42 +11:00
Benjamin Herrenschmidt f5abe14f88 powerpc/xive: Remove incorrect debug code
WORD2 if the TIMA isn't byte accessible and
isn't that useful to know about, take out the
pr_devel statement.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-16 23:48:04 +11:00
Benjamin Herrenschmidt fbadeb6bb1 powerpc: Cosmetic cleanup of cpuinfo_op
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-16 23:47:16 +11:00
Benjamin Herrenschmidt f5f563012a powerpc: Make newline in cpuinfo unconditional
We used to not put the newline between the CPU part and the summary
part on UP kernels. This is a rather pointless ifdef so take it out.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-16 23:47:15 +11:00
Benjamin Herrenschmidt bba9bc89b9 powerpc: Add aacraid and nvme to powernv_defconfig
These adapters can be found in a number of our systems, so let's
enable the corresponding drivers by default.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-16 23:47:15 +11:00