Commit 1ec9dd80be ("MIPS: CPS: Detect CPUs in secondary clusters")
added a check in cps_boot_secondary() that the secondary being booted is
in the same cluster as the CPU running this code. This check is
performed using current_cpu_data without disabling preemption. As such
when CONFIG_PREEMPT=y, a BUG is triggered:
[ 57.991693] BUG: using smp_processor_id() in preemptible [00000000] code: hotplug/1749
<snip>
[ 58.063077] Call Trace:
[ 58.065842] [<8040cdb4>] show_stack+0x84/0x114
[ 58.070830] [<80b11b38>] dump_stack+0xf8/0x140
[ 58.075796] [<8079b12c>] check_preemption_disabled+0xec/0x118
[ 58.082204] [<80415110>] cps_boot_secondary+0x84/0x44c
[ 58.087935] [<80413a14>] __cpu_up+0x34/0x98
[ 58.092624] [<80434240>] bringup_cpu+0x38/0x114
[ 58.097680] [<80434af0>] cpuhp_invoke_callback+0x168/0x8f0
[ 58.103801] [<804362d0>] _cpu_up+0x154/0x1c8
[ 58.108565] [<804363dc>] do_cpu_up+0x98/0xa8
[ 58.113333] [<808261f8>] device_online+0x84/0xc0
[ 58.118481] [<80826294>] online_store+0x60/0x98
[ 58.123562] [<8062261c>] kernfs_fop_write+0x158/0x1d4
[ 58.129196] [<805a2ae4>] __vfs_write+0x4c/0x168
[ 58.134247] [<805a2dc8>] vfs_write+0xe0/0x190
[ 58.139095] [<805a2fe0>] SyS_write+0x68/0xc4
[ 58.143854] [<80415d58>] syscall_common+0x34/0x58
In reality we don't currently support running the kernel on CPUs not in
cluster 0, so the answer to cpu_cluster(¤t_cpu_data) will always
be 0, even if this task being preempted and continues running on a
different CPU. Regardless, the BUG should not be triggered, so fix this
by switching to raw_current_cpu_data. When multicluster support lands
upstream this check will need removing or changing anyway.
Fixes: 1ec9dd80be ("MIPS: CPS: Detect CPUs in secondary clusters")
Signed-off-by: Matt Redfearn <matt.redfearn@mips.com>
Reviewed-by: Paul Burton <paul.burton@mips.com>
CC: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17563/
Signed-off-by: James Hogan <jhogan@kernel.org>
Commit 6f542ebeae ("MIPS: Fix race on setting and getting
cpu_online_mask") effectively reverted commit 8f46cca1e6 ("MIPS: SMP:
Fix possibility of deadlock when bringing CPUs online") and thus has
reinstated the possibility of deadlock.
The commit was based on testing of kernel v4.4, where the CPU hotplug
core code issued a BUG() if the starting CPU is not marked online when
the boot CPU returns from __cpu_up. The commit fixes this race (in
v4.4), but re-introduces the deadlock situation.
As noted in the commit message, upstream differs in this area. Commit
8df3e07e7f ("cpu/hotplug: Let upcoming cpu bring itself fully up")
adds a completion event in the CPU hotplug core code, making this race
impossible. However, people were unhappy with relying on the core code
to do the right thing.
To address the issues both commits were trying to fix, add a second
completion event in the MIPS smp hotplug path. It removes the
possibility of a race, since the MIPS smp hotplug code now synchronises
both the boot and secondary CPUs before they return to the hotplug core
code. It also addresses the deadlock by ensuring that the secondary CPU
is not marked online before it's counters are synchronised.
This fix should also be backported to fix the race condition introduced
by the backport of commit 8f46cca1e6 ("MIPS: SMP: Fix possibility of
deadlock when bringing CPUs online"), through really that race only
existed before commit 8df3e07e7f ("cpu/hotplug: Let upcoming cpu
bring itself fully up").
Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Fixes: 6f542ebeae ("MIPS: Fix race on setting and getting cpu_online_mask")
CC: Matija Glavinic Pecotic <matija.glavinic-pecotic.ext@nokia.com>
Cc: <stable@vger.kernel.org> # v4.1+: 8f46cca1e6c0: "MIPS: SMP: Fix possibility of deadlock when bringing CPUs online"
Cc: <stable@vger.kernel.org> # v4.1+: a00eeede507c: "MIPS: SMP: Use a completion event to signal CPU up"
Cc: <stable@vger.kernel.org> # v4.1+: 6f542ebeaee0: "MIPS: Fix race on setting and getting cpu_online_mask"
Cc: <stable@vger.kernel.org> # v4.1+
Patchwork: https://patchwork.linux-mips.org/patch/17376/
Signed-off-by: James Hogan <jhogan@kernel.org>
Commit e83f7e02af ("MIPS: CPS: Have asm/mips-cps.h include CM & CPC
headers") adds a #error to arch/mips/include/asm/mips-cpc.h if it is
included directly. While this commit replaced almost all direct includes
of mips-cm.h and mips-cpc.h, 2 remain.
With some defconfigs, mips-cps.h is indirectly included before
mips-cpc.h, but in others this results in compilation errors:
In file included from arch/mips/generic/init.c:23:0:
./arch/mips/include/asm/mips-cpc.h:12:3: error: #error Please include
asm/mips-cps.h rather than asm/mips-cpc.h
# error Please include asm/mips-cps.h rather than asm/mips-cpc.h
In file included from arch/mips/kernel/smp.c:23:0:
./arch/mips/include/asm/mips-cpc.h:12:3: error: #error Please include
asm/mips-cps.h rather than asm/mips-cpc.h
# error Please include asm/mips-cps.h rather than asm/mips-cpc.h
In both cases, fix this by including mips-cps.h instead.
Fixes: e83f7e02af ("MIPS: CPS: Have asm/mips-cps.h include CM & CPC headers")
Signed-off-by: Matt Redfearn <matt.redfearn@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/17492/
Signed-off-by: James Hogan <jhogan@kernel.org>
MIPS will soon not be a part of Imagination Technologies, and as such
many @imgtec.com email addresses will no longer be valid. This patch
updates the addresses for those who:
- Have 10 or more patches in mainline authored using an @imgtec.com
email address, or any patches dated within the past year.
- Are still with Imagination but leaving as part of the MIPS business
unit, as determined from an internal email address list.
- Haven't already updated their email address (ie. JamesH) or expressed
a desire to be excluded (ie. Maciej).
- Acked v2 or earlier of this patch, which leaves Deng-Cheng, Matt &
myself.
New addresses are of the form firstname.lastname@mips.com, and all
verified against an internal email address list. An entry is added to
.mailmap for each person such that get_maintainer.pl will report the new
addresses rather than @imgtec.com addresses which will soon be dead.
Instances of the affected addresses throughout the tree are then
mechanically replaced with the new @mips.com address.
Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: Deng-Cheng Zhu <dengcheng.zhu@imgtec.com>
Cc: Deng-Cheng Zhu <dengcheng.zhu@mips.com>
Acked-by: Dengcheng Zhu <dengcheng.zhu@mips.com>
Cc: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: Matt Redfearn <matt.redfearn@mips.com>
Acked-by: Matt Redfearn <matt.redfearn@mips.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Cc: trivial@kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/17540/
Signed-off-by: James Hogan <jhogan@kernel.org>
Please do not apply this to mainline directly, instead please re-run the
coccinelle script shown below and apply its output.
For several reasons, it is desirable to use {READ,WRITE}_ONCE() in
preference to ACCESS_ONCE(), and new code is expected to use one of the
former. So far, there's been no reason to change most existing uses of
ACCESS_ONCE(), as these aren't harmful, and changing them results in
churn.
However, for some features, the read/write distinction is critical to
correct operation. To distinguish these cases, separate read/write
accessors must be used. This patch migrates (most) remaining
ACCESS_ONCE() instances to {READ,WRITE}_ONCE(), using the following
coccinelle script:
----
// Convert trivial ACCESS_ONCE() uses to equivalent READ_ONCE() and
// WRITE_ONCE()
// $ make coccicheck COCCI=/home/mark/once.cocci SPFLAGS="--include-headers" MODE=patch
virtual patch
@ depends on patch @
expression E1, E2;
@@
- ACCESS_ONCE(E1) = E2
+ WRITE_ONCE(E1, E2)
@ depends on patch @
expression E;
@@
- ACCESS_ONCE(E)
+ READ_ONCE(E)
----
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: davem@davemloft.net
Cc: linux-arch@vger.kernel.org
Cc: mpe@ellerman.id.au
Cc: shuah@kernel.org
Cc: snitzer@redhat.com
Cc: thor.thayer@linux.intel.com
Cc: tj@kernel.org
Cc: viro@zeniv.linux.org.uk
Cc: will.deacon@arm.com
Link: http://lkml.kernel.org/r/1508792849-3115-19-git-send-email-paulmck@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The only user of thread_saved_pc() in non-arch-specific code was removed
in commit 8243d55977 ("sched/core: Remove pointless printout in
sched_show_task()"), so it no longer needs to be globally defined for
MIPS and can be made static.
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/17303/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Commit c311c79799 ("cpumask: make "nr_cpumask_bits" unsigned")
modified mipspmu_event_init() to cast the struct perf_event cpu field to
an unsigned integer before it is compared with nr_cpumask_bits (and
*ahem* did so without copying the linux-mips mailing list or any MIPS
developers...). This is broken because the cpu field may be -1 for
events which follow a process rather than being affine to a particular
CPU. When this is the case the cast to an unsigned int results in a
value equal to ULONG_MAX, which is always greater than nr_cpumask_bits
so we always fail mipspmu_event_init() and return -ENODEV.
The check against nr_cpumask_bits seems nonsensical anyway, so this
patch simply removes it. The cpu field is going to either be -1 or a
valid CPU number. Comparing it with nr_cpumask_bits is effectively
checking that it's a valid cpu number, but it seems safe to rely on the
core perf events code to ensure that's the case.
The end result is that this fixes use of perf on MIPS when not
constraining events to a particular CPU, and fixes the "perf list hw"
command which fails to list any events without this.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Fixes: c311c79799 ("cpumask: make "nr_cpumask_bits" unsigned")
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: linux-mips@linux-mips.org
Cc: stable <stable@vger.kernel.org> # v4.12+
Patchwork: https://patchwork.linux-mips.org/patch/17323/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Pull MIPS updates from Ralf Baechle:
"This is the main pull request for 4.14 for MIPS; below a summary of
the non-merge commits:
CM:
- Rename mips_cm_base to mips_gcr_base
- Specify register size when generating accessors
- Use BIT/GENMASK for register fields, order & drop shifts
- Add cluster & block args to mips_cm_lock_other()
CPC:
- Use common CPS accessor generation macros
- Use BIT/GENMASK for register fields, order & drop shifts
- Introduce register modify (set/clear/change) accessors
- Use change_*, set_* & clear_* where appropriate
- Add CM/CPC 3.5 register definitions
- Use GlobalNumber macros rather than magic numbers
- Have asm/mips-cps.h include CM & CPC headers
- Cluster support for topology functions
- Detect CPUs in secondary clusters
CPS:
- Read GIC_VL_IDENT directly, not via irqchip driver
DMA:
- Consolidate coherent and non-coherent dma_alloc code
- Don't use dma_cache_sync to implement fd_cacheflush
FPU emulation / FP assist code:
- Another series of 14 commits fixing corner cases such as NaN
propgagation and other special input values.
- Zero bits 32-63 of the result for a CLASS.D instruction.
- Enhanced statics via debugfs
- Do not use bools for arithmetic. GCC 7.1 moans about this.
- Correct user fault_addr type
Generic MIPS:
- Enhancement of stack backtraces
- Cleanup from non-existing options
- Handle non word sized instructions when examining frame
- Fix detection and decoding of ADDIUSP instruction
- Fix decoding of SWSP16 instruction
- Refactor handling of stack pointer in get_frame_info
- Remove unreachable code from force_fcr31_sig()
- Convert to using %pOF instead of full_name
- Remove the R6000 support.
- Move FP code from *_switch.S to *_fpu.S
- Remove unused ST_OFF from r2300_switch.S
- Allow platform to specify multiple its.S files
- Add #includes to various files to ensure code builds reliable and
without warning..
- Remove __invalidate_kernel_vmap_range
- Remove plat_timer_setup
- Declare various variables & functions static
- Abstract CPU core & VP(E) ID access through accessor functions
- Store core & VP IDs in GlobalNumber-style variable
- Unify checks for sibling CPUs
- Add CPU cluster number accessors
- Prevent direct use of generic_defconfig
- Make CONFIG_MIPS_MT_SMP default y
- Add __ioread64_copy
- Remove unnecessary inclusions of linux/irqchip/mips-gic.h
GIC:
- Introduce asm/mips-gic.h with accessor functions
- Use new GIC accessor functions in mips-gic-timer
- Remove counter access functions from irq-mips-gic.c
- Remove gic_read_local_vp_id() from irq-mips-gic.c
- Simplify shared interrupt pending/mask reads in irq-mips-gic.c
- Simplify gic_local_irq_domain_map() in irq-mips-gic.c
- Drop gic_(re)set_mask() functions in irq-mips-gic.c
- Remove gic_set_polarity(), gic_set_trigger(), gic_set_dual_edge(),
gic_map_to_pin() and gic_map_to_vpe() from irq-mips-gic.c.
- Convert remaining shared reg access, local int mask access and
remaining local reg access to new accessors
- Move GIC_LOCAL_INT_* to asm/mips-gic.h
- Remove GIC_CPU_INT* macros from irq-mips-gic.c
- Move various definitions to the driver
- Remove gic_get_usm_range()
- Remove __gic_irq_dispatch() forward declaration
- Remove gic_init()
- Use mips_gic_present() in place of gic_present and remove
gic_present
- Move gic_get_c0_*_int() to asm/mips-gic.h
- Remove linux/irqchip/mips-gic.h
- Inline __gic_init()
- Inline gic_basic_init()
- Make pcpu_masks a per-cpu variable
- Use pcpu_masks to avoid reading GIC_SH_MASK*
- Clean up mti, reserved-cpu-vectors handling
- Use cpumask_first_and() in gic_set_affinity()
- Let the core set struct irq_common_data affinity
microMIPS:
- Fix microMIPS stack unwinding on big endian systems
MIPS-GIC:
- SYNC after enabling GIC region
NUMA:
- Remove the unused parent_node() macro
R6:
- Constify r2_decoder_tables
- Add accessor & bit definitions for GlobalNumber
SMP:
- Constify smp ops
- Allow boot_secondary SMP op to return errors
VDSO:
- Drop gic_get_usm_range() usage
- Avoid use of linux/irqchip/mips-gic.h
Platform changes:
Alchemy:
- Add devboard machine type to cpuinfo
- update cpu feature overrides
- Threaded carddetect irqs for devboards
AR7:
- allow NULL clock for clk_get_rate
BCM63xx:
- Fix ENETDMA_6345_MAXBURST_REG offset
- Allow NULL clock for clk_get_rate
CI20:
- Enable GPIO and RTC drivers in defconfig
- Add ethernet and fixed-regulator nodes to DTS
Generic platform:
- Move Boston and NI 169445 FIT image source to their own files
- Include asm/bootinfo.h for plat_fdt_relocated()
- Include asm/time.h for get_c0_*_int()
- Include asm/bootinfo.h for plat_fdt_relocated()
- Include asm/time.h for get_c0_*_int()
- Allow filtering enabled boards by requirements
- Don't explicitly disable CONFIG_USB_SUPPORT
- Bump default NR_CPUS to 16
JZ4700:
- Probe the jz4740-rtc driver from devicetree
Lantiq:
- Drop check of boot select from the spi-falcon driver.
- Drop check of boot select from the lantiq-flash MTD driver.
- Access boot cause register in the watchdog driver through regmap
- Add device tree binding documentation for the watchdog driver
- Add docs for the RCU DT bindings.
- Convert the fpi bus driver to a platform_driver
- Remove ltq_reset_cause() and ltq_boot_select(
- Switch to a proper reset driver
- Switch to a new drivers/soc GPHY driver
- Add an USB PHY driver for the Lantiq SoCs using the RCU module
- Use of_platform_default_populate instead of __dt_register_buses
- Enable MFD_SYSCON to be able to use it for the RCU MFD
- Replace ltq_boot_select() with dummy implementation.
Loongson 2F:
- Allow NULL clock for clk_get_rate
Malta:
- Use new GIC accessor functions
NI 169445:
- Add support for NI 169445 board.
- Only include in 32r2el kernels
Octeon:
- Add support for watchdog of 78XX SOCs.
- Add support for watchdog of CN68XX SOCs.
- Expose support for mips32r1, mips32r2 and mips64r1
- Enable more drivers in config file
- Add support for accessing the boot vector.
- Remove old boot vector code from watchdog driver
- Define watchdog registers for 70xx, 73xx, 78xx, F75xx.
- Make CSR functions node aware.
- Allow access to CIU3 IRQ domains.
- Misc cleanups in the watchdog driver
Omega2+:
- New board, add support and defconfig
Pistachio:
- Enable Root FS on NFS in defconfig
Ralink:
- Add Mediatek MT7628A SoC
- Allow NULL clock for clk_get_rate
- Explicitly request exclusive reset control in the pci-mt7620 PCI driver.
SEAD3:
- Only include in 32 bit kernels by default
VoCore:
- Add VoCore as a vendor t0 dt-bindings
- Add defconfig file"
* '4.14-features' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (167 commits)
MIPS: Refactor handling of stack pointer in get_frame_info
MIPS: Stacktrace: Fix microMIPS stack unwinding on big endian systems
MIPS: microMIPS: Fix decoding of swsp16 instruction
MIPS: microMIPS: Fix decoding of addiusp instruction
MIPS: microMIPS: Fix detection of addiusp instruction
MIPS: Handle non word sized instructions when examining frame
MIPS: ralink: allow NULL clock for clk_get_rate
MIPS: Loongson 2F: allow NULL clock for clk_get_rate
MIPS: BCM63XX: allow NULL clock for clk_get_rate
MIPS: AR7: allow NULL clock for clk_get_rate
MIPS: BCM63XX: fix ENETDMA_6345_MAXBURST_REG offset
mips: Save all registers when saving the frame
MIPS: Add DWARF unwinding to assembly
MIPS: Make SAVE_SOME more standard
MIPS: Fix issues in backtraces
MIPS: jz4780: DTS: Probe the jz4740-rtc driver from devicetree
MIPS: Ci20: Enable RTC driver
watchdog: octeon-wdt: Add support for 78XX SOCs.
watchdog: octeon-wdt: Add support for cn68XX SOCs.
watchdog: octeon-wdt: File cleaning.
...
Pull more set_fs removal from Al Viro:
"Christoph's 'use kernel_read and friends rather than open-coding
set_fs()' series"
* 'work.set_fs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
fs: unexport vfs_readv and vfs_writev
fs: unexport vfs_read and vfs_write
fs: unexport __vfs_read/__vfs_write
lustre: switch to kernel_write
gadget/f_mass_storage: stop messing with the address limit
mconsole: switch to kernel_read
btrfs: switch write_buf to kernel_write
net/9p: switch p9_fd_read to kernel_write
mm/nommu: switch do_mmap_private to kernel_read
serial2002: switch serial2002_tty_write to kernel_{read/write}
fs: make the buf argument to __kernel_write a void pointer
fs: fix kernel_write prototype
fs: fix kernel_read prototype
fs: move kernel_read to fs/read_write.c
fs: move kernel_write to fs/read_write.c
autofs4: switch autofs4_write to __kernel_write
ashmem: switch to ->read_iter
Pull namespace updates from Eric Biederman:
"Life has been busy and I have not gotten half as much done this round
as I would have liked. I delayed it so that a minor conflict
resolution with the mips tree could spend a little time in linux-next
before I sent this pull request.
This includes two long delayed user namespace changes from Kirill
Tkhai. It also includes a very useful change from Serge Hallyn that
allows the security capability attribute to be used inside of user
namespaces. The practical effect of this is people can now untar
tarballs and install rpms in user namespaces. It had been suggested to
generalize this and encode some of the namespace information
information in the xattr name. Upon close inspection that makes the
things that should be hard easy and the things that should be easy
more expensive.
Then there is my bugfix/cleanup for signal injection that removes the
magic encoding of the siginfo union member from the kernel internal
si_code. The mips folks reported the case where I had used FPE_FIXME
me is impossible so I have remove FPE_FIXME from mips, while at the
same time including a return statement in that case to keep gcc from
complaining about unitialized variables.
I almost finished the work to get make copy_siginfo_to_user a trivial
copy to user. The code is available at:
git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace.git neuter-copy_siginfo_to_user-v3
But I did not have time/energy to get the code posted and reviewed
before the merge window opened.
I was able to see that the security excuse for just copying fields
that we know are initialized doesn't work in practice there are buggy
initializations that don't initialize the proper fields in siginfo. So
we still sometimes copy unitialized data to userspace"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
Introduce v3 namespaced file capabilities
mips/signal: In force_fcr31_sig return in the impossible case
signal: Remove kernel interal si_code magic
fcntl: Don't use ambiguous SIG_POLL si_codes
prctl: Allow local CAP_SYS_ADMIN changing exe_file
security: Use user_namespace::level to avoid redundant iterations in cap_capable()
userns,pidns: Verify the userns for new pid namespaces
signal/testing: Don't look for __SI_FAULT in userspace
signal/mips: Document a conflict with SI_USER with SIGFPE
signal/sparc: Document a conflict with SI_USER with SIGFPE
signal/ia64: Document a conflict with SI_USER with SIGFPE
signal/alpha: Document a conflict with SI_USER for SIGTRAP
Commit 34c2f668d0 ("MIPS: microMIPS: Add unaligned access support.")
added handling of microMIPS instructions to manipulate the stack
pointer. The code that was added violates code style rules with long
lines caused by lots of nested conditionals.
The added code interprets (inline) any known stack pointer manipulation
instruction to find the stack frame size. Handling the microMIPS cases
added quite a bit of complication to this function.
Refactor is_sp_move_ins to perform the interpretation of the immediate
as the instruction manipulating the stack pointer is found. This reduces
the amount of indentation required in get_frame_info, and more closely
matches the operation of is_ra_save_ins.
Suggested-by: Maciej W. Rozycki <macro@imgtec.com>
Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: Marcin Nowakowski <marcin.nowakowski@imgtec.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/16958/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The stack unwinding code uses the mips_instuction union to decode the
instructions it finds. That union uses the __BITFIELD_FIELD macro to
reorder depending on endianness. The stack unwinding code always places
16bit instructions in halfword 1 of the union. This makes the union
accesses correct for little endian systems. Similarly, 32bit
instructions are reordered such that they are correct for little endian
systems. This handling leaves unwinding the stack on big endian systems
broken, as the mips_instruction union will then look for the fields in
the wrong halfword.
To fix this, use a logical shift to place the 16bit instruction into the
correct position in the word field of the union. Use the same shifting
to order the 2 halfwords of 32bit instuctions. Then replace accesses to
the halfword with accesses to the shifted word.
In the case of the ADDIUS5 instruction, switch to using the
mm16_r5_format union member to avoid the need for a 16bit shift.
Fixes: 34c2f668d0 ("MIPS: microMIPS: Add unaligned access support.")
Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Reviewed-by: James Hogan <james.hogan@imgtec.com>
Cc: Marcin Nowakowski <marcin.nowakowski@imgtec.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/16956/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
When the immediate encoded in the instruction is accessed, it is sign
extended due to being a signed value being assigned to a signed integer.
The ISA specifies that this operation is an unsigned operation.
The sign extension leads us to incorrectly decode:
801e9c8e: cbf1 sw ra,68(sp)
As having an immediate of 1073741809.
Since the instruction format does not specify signed/unsigned, and this
is currently the only location to use this instuction format, change it
to an unsigned immediate.
Fixes: bb9bc4689b ("MIPS: Calculate microMIPS ra properly when unwinding the stack")
Suggested-by: Paul Burton <paul.burton@imgtec.com>
Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Reviewed-by: James Hogan <james.hogan@imgtec.com>
Cc: Marcin Nowakowski <marcin.nowakowski@imgtec.com>
Cc: Miodrag Dinic <miodrag.dinic@imgtec.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: David Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/16957/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Commit 34c2f668d0 ("MIPS: microMIPS: Add unaligned access support.")
added handling of microMIPS instructions to manipulate the stack
pointer. Unfortunately the decoding of the addiusp instruction was
incorrect, and performed a left shift by 2 bits to the raw immediate,
rather than decoding the immediate and then performing the shift, as
documented in the ISA.
This led to incomplete stack traces, due to incorrect frame sizes being
calculated. For example the instruction:
801faee0 <do_sys_poll>:
801faee0: 4e25 addiu sp,sp,-952
As decoded by objdump, would be interpreted by the existing code as
having manipulated the stack pointer by +1096.
Fix this by changing the order of decoding the immediate and applying
the left shift. Also change to accessing the instuction through the
union to avoid the endianness problem of accesing halfword[0], which
will fail on big endian systems.
Cope with the special behaviour of immediates 0x0, 0x1, 0x1fe and 0x1ff
by XORing with 0x100 again if mod(immediate) < 4. This logic was tested
with the following test code:
int main(int argc, char **argv)
{
unsigned int enc;
int imm;
for (enc = 0; enc < 512; ++enc) {
int tmp = enc << 2;
imm = -(signed short)(tmp | ((tmp & 0x100) ? 0xfe00 : 0));
unsigned short tmp = enc;
tmp = (tmp ^ 0x100) - 0x100;
if ((unsigned short)(tmp + 2) < 4)
tmp ^= 0x100;
imm = -(signed short)(tmp << 2);
printf("%#x\t%d\t->\t(%#x\t%d)\t%#x\t%d\n",
enc, enc,
(short)tmp, (short)tmp,
imm, imm);
}
return EXIT_SUCCESS;
}
Which generates the table:
input encoding -> tmp (matching manual) frame size
-----------------------------------------------------------------------
0 0 -> (0x100 256) 0xfffffc00 -1024
0x1 1 -> (0x101 257) 0xfffffbfc -1028
0x2 2 -> (0x2 2) 0xfffffff8 -8
0x3 3 -> (0x3 3) 0xfffffff4 -12
...
0xfe 254 -> (0xfe 254) 0xfffffc08 -1016
0xff 255 -> (0xff 255) 0xfffffc04 -1020
0x100 256 -> (0xffffff00 -256) 0x400 1024
0x101 257 -> (0xffffff01 -255) 0x3fc 1020
...
0x1fc 508 -> (0xfffffffc -4) 0x10 16
0x1fd 509 -> (0xfffffffd -3) 0xc 12
0x1fe 510 -> (0xfffffefe -258) 0x408 1032
0x1ff 511 -> (0xfffffeff -257) 0x404 1028
Thanks to James Hogan for the test code & verifying the logic.
Fixes: 34c2f668d0 ("MIPS: microMIPS: Add unaligned access support.")
Suggested-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: Marcin Nowakowski <marcin.nowakowski@imgtec.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/16955/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The addiusp instruction uses the pool16d opcode, with bit 0 of the
immediate set. The test for the addiusp opcode erroneously did a logical
and of the immediate with mm_addiusp_func, which has value 1, so this
test always passes when the immediate is non-zero.
Fix the test by replacing the logical and with a bitwise and.
Fixes: 34c2f668d0 ("MIPS: microMIPS: Add unaligned access support.")
Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: Marcin Nowakowski <marcin.nowakowski@imgtec.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/16954/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Commit 34c2f668d0 ("MIPS: microMIPS: Add unaligned access support.")
added fairly broken support for handling 16bit microMIPS instructions in
get_frame_info(). It adjusts the instruction pointer by 16bits in the
case of a 16bit sp move instruction, but not any other 16bit
instruction.
Commit b6c7a324df ("MIPS: Fix get_frame_info() handling of microMIPS
function size") goes some way to fixing get_frame_info() to iterate over
microMIPS instuctions, but the instruction pointer is still manipulated
using a postincrement, and is of union mips_instruction type. Since the
union is sized to the largest member (a word), but microMIPS
instructions are a mix of halfword and word sizes, the function does not
always iterate correctly, ending up misaligned with the instruction
stream and interpreting it incorrectly.
Since the instruction modifying the stack pointer is usually the first
in the function, that one is usually handled correctly. But the
instruction which saves the return address to the sp is some variable
number of instructions into the frame and is frequently missed due to
not being on a word boundary, leading to incomplete walking of the
stack.
Fix this by incrementing the instruction pointer based on the size of
the previously decoded instruction (& remove the hack introduced by
commit 34c2f668d0 ("MIPS: microMIPS: Add unaligned access support.")
which adjusts the instruction pointer in the case of a 16bit sp move
instruction, but not any other).
Fixes: 34c2f668d0 ("MIPS: microMIPS: Add unaligned access support.")
Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: Marcin Nowakowski <marcin.nowakowski@imgtec.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/16953/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
I saw two problems when doing backtraces:
The compiler was putting a "fast return" at the top of some
functions, before it set up the frame. The backtrace code
would stop when it saw a jump instruction, so it would never
get to the stack frame setup and would thus misinterpret it.
To fix this, don't look for jump instructions until the
frame setup has been seen.
The assembly code here is:
ffffffff80b885a0 <serial8250_handle_irq>:
ffffffff80b885a0: c8a00003 bbit0 a1,0x0,ffffffff80b885b0 <serial8250_handle_irq+0x10>
ffffffff80b885a4: 0000102d move v0,zero
ffffffff80b885a8: 03e00008 jr ra
ffffffff80b885ac: 00000000 nop
ffffffff80b885b0: 67bdffd0 daddiu sp,sp,-48
ffffffff80b885b4: ffb00008 sd s0,8(sp)
The second problem was the compiler was putting the last
instruction of the frame save in the delay slot of the
jump instruction. If it saved the RA in there, the
backtrace could would miss it and misinterpret the frame.
To fix this, make sure to process the instruction after
the first jump seen.
The assembly code for this is:
ffffffff80806fd0 <plat_irq_dispatch>:
ffffffff80806fd0: 67bdffd0 daddiu sp,sp,-48
ffffffff80806fd4: ffb30020 sd s3,32(sp)
ffffffff80806fd8: 24130018 li s3,24
ffffffff80806fdc: ffb20018 sd s2,24(sp)
ffffffff80806fe0: 3c12811c lui s2,0x811c
ffffffff80806fe4: ffb10010 sd s1,16(sp)
ffffffff80806fe8: 3c11811c lui s1,0x811c
ffffffff80806fec: ffb00008 sd s0,8(sp)
ffffffff80806ff0: 3c10811c lui s0,0x811c
ffffffff80806ff4: 08201c03 j ffffffff8080700c <plat_irq_dispa
tch+0x3c>
ffffffff80806ff8: ffbf0028 sd ra,40(sp)
Signed-off-by: Corey Minyard <cminyard@mvista.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/16992/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Use proper ssize_t and size_t types for the return value and count
argument, move the offset last and make it an in/out argument like
all other read/write helpers, and make the buf argument a void pointer
to get rid of lots of casts in the callers.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
linux/irqchip/mips-gic.h is included in a few files that don't actually
use it at all. Remove these unnecessary inclusions in preparation for
removing the header.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17048/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
In preparation for removing the gic_present global variable, switch to
using the mips_gic_present() function instead. For the most part this is
a straightforward substitution. In cases which previously wrapped the
GIC case in an #ifdef CONFIG_MIPS_GIC that #ifdef has been removed,
since mips_gic_present() will return a compile-time constant false
allowing the affected code to be optimised out anyway.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17044/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
We don't really need gic_get_usm_range() to abstract discovery of the
address of the GIC user-visible section now that we have access to its
base address globally.
Switch to calculating it ourselves, which will allow us to stop
requiring the irqchip driver to care about a counter exposed to userland
for use via the VDSO.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17040/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Rather than calling the gic_read_local_vp_id() function from the GIC
irqchip driver, call read_gic_vl_ident() to read the GIC_VL_IDENT
register directly. This will allow us to remove gic_read_local_vp_id()
from the irqchip driver in a further patch, since that driver doesn't
actually care about the register's value.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17023/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
As a first step towards supporting multi-cluster systems, detect cores &
VPs in secondary clusters & record their cluster information in the
cpu_data array. The "VP topology" line printed during boot is extended
to display multiple clusters. On a single cluster it shows output like
the following:
VP topology: {4,4}
This would indicate a system with 2 cores which each contain 4 VPs. We
extend this to cover multiple clusters in a natural way:
VP topology: {4,4},{2,2}
This would indicate a system with 2 clusters. The first cluster contains
2 cores which each contain 4 VPs. The second cluster contains 2 cores
which each contain 2 VPs.
Actually booting these cores & VPs is left to further patches once other
pieces are in place.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17017/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Modify the functions we use to read information about the topology of
the system (the number of cores, VPs & IOCUs that it contains) in order
to take into account multiple clusters, and provide a new function to
determine the number of clusters in the system.
Users of these functions are modified only such that they continue to
build successfully - having them actually handle multiple clusters is
left to further patches.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17016/
Patchwork: https://patchwork.linux-mips.org/patch/17218/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
With Coherence Manager (CM) 3.5 information about the topology of the
system, which has previously only been available through & accessed from
the CM, is now also provided by the Cluster Power Controller (CPC). This
includes a new CPC_CONFIG register mirroring GCR_CONFIG, and similarly a
new CPC_Cx_CONFIG register mirroring GCR_Cx_CONFIG.
In preparation for adjusting functions such as mips_cm_numcores(), which
have previously only needed to access the CM, to also access the CPC
this patch modifies the way we use the various CPS headers. Rather than
having users include asm/mips-cm.h or asm/mips-cpc.h individually we
instead have users include asm/mips-cps.h which in turn includes
asm/mips-cm.h & asm/mips-cpc.h. This means that users will gain access
to both CM & CPC registers by including one header, and most importantly
it makes asm/mips-cps.h an ideal location for helper functions which
need to access the various components of the CPS.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17015/
Patchwork: https://patchwork.linux-mips.org/patch/17217/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Allow the boot_secondary SMP op to return an error to __cpu_up(), which
will in turn return it to its caller.
This will allow SMP implementations to return errors quickly in cases
they they know have failed, rather than relying upon __cpu_up()
eventually timing out waiting for the cpu_running completion.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17014/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
With CM >= 3.5 we have the notion of multiple clusters & can access
their CM, CPC & GIC registers via the apporpriate redirect/other
register blocks. In order to allow for this introduce cluster & block
arguments to mips_cm_lock_other() which configures the redirect/other
region to point at the appropriate cluster, core, VP & register block.
Since we now have 4 arguments to mips_cm_lock_other() & a common use is
likely to be to target the cluster, core & VP corresponding to a
particular Linux CPU number we also add a new mips_cm_lock_other_cpu()
helper function which handles that without the caller needing to
manually pull out the cluster, core & VP numbers.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17013/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Introduce cpu_cluster() & cpu_set_cluster() accessor functions in the
same vein as cpu_core(), cpu_vpe_id() & their set variants. These will
be used in further patches to allow users to get or set a CPUs cluster
number.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17012/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Up until now we have open-coded checks for whether CPUs are siblings,
with slight variations on whether we consider the package ID or not.
This will only get more complex when we introduce cluster support, so in
preparation for that this patch introduces a cpus_are_siblings()
function which can be used to check whether or not 2 CPUs are siblings
in a consistent manner.
By checking globalnumber with the VP ID masked out this also has the
neat side effect of being ready for multi-cluster systems already.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Acked-by: Rafael J. Wysocki <rjw@rjwysocki.net>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17011/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This patch modifies the way we store core & VP IDs such that we store
them in a single 32 bit integer whose format matches that of the MIPSr6
GlobalNumber register. Whereas we have previously stored core & VP IDs
in separate fields, storing them in a single GlobalNumber-like field:
1) Reduces the size of struct cpuinfo_mips by 4 bytes, and will allow
it to not grow when cluster support is added.
2) Gives us a natural place to store cluster number, which matches up
with what the architecture provides.
3) Will be useful in the future as a parameter to the MIPSr6 GINVI
instruction to specify a target CPU whose icache that instruction
should operate on.
The cpu_set*() accessor functions are moved out of the asm/cpu-info.h
header in order to allow them to use the WARN_ON macro, which is
unusable in asm/cpu-info.h due to include ordering.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17010/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
We currently have fields in struct cpuinfo_mips for the core & VP(E) ID
of a particular CPU, and various pieces of code directly access those
fields. This patch abstracts such access by introducing accessor
functions cpu_core(), cpu_set_core(), cpu_vpe_id() & cpu_set_vpe_id()
and having code that needs to access these values call those functions
rather than directly accessing the struct cpuinfo_mips fields. This
prepares us for changes to the way in which those values are stored in
later patches.
The cpu_vpe_id() function is introduced even though we already had a
cpu_vpe_id() macro for a couple of reasons:
1) It's more consistent with the core, and future cluster, accessors.
2) It ensures a sensible return type without explicit casts.
3) It's generally preferable to use functions rather than macros.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17009/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
We now have definitions for the GlobalNumber register in asm/mipsregs.h,
so use them in place of magic numbers in cps-vec.S.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17008/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Make use of the new change_*, set_* & clear_* accessor functions for CPS
(CM, CPC & GIC) registers where doing so makes the code easier to read
or shortens it without adversely affecting readability.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17005/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Tidy up asm/mips-cpc.h in a similar way to what "MIPS: CM: Use
BIT/GENMASK for register fields, order & drop shifts" did for
asm/mips-cm.h.
We use BIT() & GENMASK() to simplify the definition of register fields,
drop the _SHF definitions since that information can be found in the
_MSK ones, and then drop the _MSK suffix.
Fields definitions are moved to be next to the appropriate register
definition, making it easier to link the two & keep everything ordered
by register address. Comments are added including the name of each
register & a brief description of its purpose which helps to understand
what registers are for, link them back to hardware documentation or grep
for them.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17003/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
If a restartable syscall is called using the indirect o32 syscall
handler - eg: syscall(__NR_waitid, ...), then it is possible for the
incorrect arguments to be passed to the syscall after it has been
restarted. This is because the syscall handler tries to shift all the
registers down one place in pt_regs so that when the syscall is restarted,
the "real" syscall is called instead. Unfortunately it only shifts the
arguments passed in registers, not the arguments on the user stack. This
causes the 4th argument to be duplicated when the syscall is restarted.
Fix by removing all the pt_regs shifting so that the indirect syscall
handler is called again when the syscall is restarted. The comment "some
syscalls like execve get their arguments from struct pt_regs" is long
out of date so this should now be safe.
Signed-off-by: James Cowgill <James.Cowgill@imgtec.com>
Reviewed-by: James Hogan <james.hogan@imgtec.com>
Tested-by: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/15856/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Since commit 669c409222 ("MIPS: Give __secure_computing() access to
syscall arguments."), upon syscall entry when seccomp is enabled,
syscall_trace_enter() passes a carefully prepared struct seccomp_data
containing syscall arguments to __secure_computing(). Unfortunately it
directly uses mips_get_syscall_arg() and fails to take into account the
indirect O32 system calls (i.e. syscall(2)) which put the system call
number in a0 and have the arguments shifted up by one entry.
We can't just revert that commit as samples/bpf/tracex5 would break
again, so use syscall_get_arguments() which already takes indirect
syscalls into account instead of directly using mips_get_syscall_arg(),
similar to what populate_seccomp_data() does.
This also removes the redundant error checking of the
mips_get_syscall_arg() return value (get_user() already zeroes the
result if an argument from the stack can't be loaded).
Reported-by: James Cowgill <James.Cowgill@imgtec.com>
Fixes: 669c409222 ("MIPS: Give __secure_computing() access to syscall arguments.")
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: David Daney <david.daney@cavium.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Will Drewry <wad@chromium.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: netdev@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16994/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
There's no reason for us not to use BIT() & GENMASK() in asm/mips-cm.h
when declaring macros corresponding to register fields. This patch
modifies our definitions to do so.
The *_SHF definitions are removed entirely - they duplicate information
found in the masks, are infrequently used & can be replaced with use of
__ffs() where needed.
The *_MSK definitions then lose their _MSK suffix which is now somewhat
redundant, and users are modified to match.
The field definitions are moved to follow the appropriate register's
accessor functions, which helps to keep the field definitions in order &
to find the appropriate fields for a given register. Whilst here a
comment is added describing each register & including its name, which is
helpful both for linking the register back to hardware documentation &
for grepping purposes.
This also cleans up a couple of issues that became obvious as a result
of making the changes described above:
- We previously had definitions for GCR_Cx_RESET_EXT_BASE & a phony
copy of that named GCR_RESET_EXT_BASE - a register which does not
exist. The bad definitions were added by commit 497e803ebf ("MIPS:
smp-cps: Ensure secondary cores start with EVA disabled") and made
use of from boot_core(), which is now modified to use the
GCR_Cx_RESET_EXT_BASE definitions.
- We had a typo in CM_GCR_ERROR_CAUSE_ERRINGO_MSK - we now correctly
define this as inFo rather than inGo.
Now that we don't duplicate field information between _SHF & _MSK
definitions, and keep the fields next to the register accessors, it will
be much easier to spot & prevent any similar oddities being introduced
in the future.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17001/
Patchwork: https://patchwork.linux-mips.org/patch/17216/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Some CM registers are always 32 bits, or at least only use bits in the
lower 32 bits of the register. For these registers it is wasteful for us
to generate accessors which bother to check mips_cm_is64 & perform 64
bit accesses.
This patch modifies the accessor generation to take into account the
size of the register, and for 32 bit registers we generate accessors
which only ever perform 32 bit accesses. For 64 bit registers we either
perform a 64 bit access or two 32 bit accesses, depending upon the value
of mips_cm_is64. Doing this saves us ~1.5KiB of code in a generic 64r6el
kernel, and perhaps more importantly simplifies various code paths.
This removes the read64_gcr_* accessors, so mips_cm_error_report() is
modified to stop using them & instead use the regular read_gcr_*
accessors which will return 64 bit values from the 64 bit registers.
The new accessor macros are placed in asm/mips-cps.h such that they can
be shared by CPC & GIC code in later patches.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17000/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
We currently have a mips_cm_base variable which holds the base address
of the Coherence Manager (CM) Global Configuration Registers (GCRs), and
accessor functions which use the GCR in their names. This works fine,
but gets in the way of sharing the code to generate the accessor
functions with other blocks (ie. CPC & GIC) because that code would then
need to separately handle the name of the base address variable & the
name used in the accessor functions.
In order to prepare for sharing the accessor generation code between CM,
CPC & GIC code this patch renames mips_cm_base to mips_gcr_base such
that the "gcr" portion is common to both the base address variable & the
accessor function names.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16999/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
We currently have various variables & functions which are only used
within a single translation unit, but which we don't declare static.
This causes various sparse warnings of the form:
arch/mips/kernel/mips-r2-to-r6-emul.c:49:1: warning: symbol
'mipsr2emustats' was not declared. Should it be static?
arch/mips/kernel/unaligned.c:1381:11: warning: symbol 'reg16to32st'
was not declared. Should it be static?
arch/mips/mm/mmap.c:146:15: warning: symbol 'arch_mmap_rnd' was not
declared. Should it be static?
Fix these & others by declaring various affected variables & functions
static, avoiding the sparse warnings & redundant symbols.
[ralf@linux-mips.org: Add Marcin's build fix.]
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: trivial@kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/17176/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The plat_timer_setup() function is entirely unused - nothing calls it,
and no platforms provide it. Perhaps our dummy implementation was once
useful as an aid in forward porting platforms, but its time has long
since passed so let's remove the dead code.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: trivial@kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/17175/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
arch/mips/kernel/idle.c provides our implementation of the
arch_cpu_idle() function, but doesn't include the linux/cpu.h header
which declares it. This leads to a warning from sparse:
arch/mips/kernel/idle.c:256:6: warning: symbol 'arch_cpu_idle' was not
declared. Should it be static?
Fix this by including linux/cpu.h to get the declaration of
arch_cpu_idle().
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: trivial@kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/17169/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Commit 1a3d59579b ("MIPS: Tidy up FPU context switching") removed
usage of ST_OFF, leaving it behind as dead code. Commit 828d1e4e98
("MIPS: Remove dead define of ST_OFF") then removed the definition of
ST_OFF from r4k_switch.S as a cleanup. However the unused definition of
ST_OFF has been left behind in r2300_switch.S. Remove it.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16239/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Move _save_fp(), _restore_fp() & _init_fpu() out of r2300_switch.S &
into r2300_fpu.S. This logically places all FP-related asm code into
r2300_fpu.S & provides consistency with R4K after the preceding commit.
Besides cleaning up this will be useful for later patches which disable
FP support.
[ralf@linux-mips.org: Fixed build issues reported by Arnd Bergmann
<arnd@arndb.de>]
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16238/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Move _save_fp(), _restore_fp(), _save_msa(), _restore_msa(),
_init_msa_upper() & _init_fpu() out of r4k_switch.S & into r4k_fpu.S.
This allows us to clean up the way in which Octeon includes the default
r4k implementations of these FP functions despite replacing resume(),
and makes CONFIG_R4K_FPU more straightforwardly represent all
configurations that have an R4K-style FPU, including Octeon.
Besides cleaning up this will be useful for later patches which disable
FP support.
[ralf@linux-mips.org: Fixed build issues reported by Arnd Bergmann
<arnd@arndb.de>]
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16237/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The kernel contains a small amount of incomplete code aimed at
supporting old R6000 CPUs. This is:
- Unused, as no machine selects CONFIG_SYS_HAS_CPU_R6000.
- Broken, since there are glaring errors such as r6000_fpu.S moving
the FCSR register to t1, then ignoring it & instead saving t0 into
struct sigcontext...
- A maintenance headache, since it's code that nobody can test which
nevertheless imposes constraints on code which it shares with other
machines.
Remove this incomplete & broken R6000 CPU support in order to clean up
and in preparation for changes which will no longer need to consider
dragging the pretense of R6000 support along with them.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16236/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The r2_decoder_tables are never modified. They are arrays of constant
values and as such should be declared const.
This change saves 256 bytes of kernel text, and 128 bytes of kernel data
(384 bytes total) on a 32r6el_defconfig (with SMP disabled)
Before:
text data bss dec hex filename
5576221 1080804 267040 6924065 69a721 vmlinux
After:
text data bss dec hex filename
5575965 1080676 267040 6923681 69a5a1 vmlinux
Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/15289/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
smp_ops providers do not modify their ops structures, so they should be
made const for robustness. Since currently the MIPS kernel is not mapped
with memory protection, this does not in itself provide any security
benefit, but it still makes sense to make this change.
There are also slight code size efficincies from the structure being
made read-only, saving 128 bytes of kernel text on a
pistachio_defconfig.
Before:
text data bss dec hex filename
7187239 1772752 470224 9430215 8fe4c7 vmlinux
After:
text data bss dec hex filename
7187111 1772752 470224 9430087 8fe447 vmlinux
Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Marcin Nowakowski <marcin.nowakowski@imgtec.com>
Cc: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Huacai Chen <chenhc@lemote.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Kevin Cernekee <cernekee@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Doug Ledford <dledford@redhat.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Joe Perches <joe@perches.com>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Steven J. Hill <steven.hill@cavium.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/16784/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
struct call_single_data is used in IPIs to transfer information between
CPUs. Its size is bigger than sizeof(unsigned long) and less than
cache line size. Currently it is not allocated with any explicit alignment
requirements. This makes it possible for allocated call_single_data to
cross two cache lines, which results in double the number of the cache lines
that need to be transferred among CPUs.
This can be fixed by requiring call_single_data to be aligned with the
size of call_single_data. Currently the size of call_single_data is the
power of 2. If we add new fields to call_single_data, we may need to
add padding to make sure the size of new definition is the power of 2
as well.
Fortunately, this is enforced by GCC, which will report bad sizes.
To set alignment requirements of call_single_data to the size of
call_single_data, a struct definition and a typedef is used.
To test the effect of the patch, I used the vm-scalability multiple
thread swap test case (swap-w-seq-mt). The test will create multiple
threads and each thread will eat memory until all RAM and part of swap
is used, so that huge number of IPIs are triggered when unmapping
memory. In the test, the throughput of memory writing improves ~5%
compared with misaligned call_single_data, because of faster IPIs.
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Huang, Ying <ying.huang@intel.com>
[ Add call_single_data_t and align with size of call_single_data. ]
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Aaron Lu <aaron.lu@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/87bmnqd6lz.fsf@yhuang-mobile.sh.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
In a recent discussion Maciej Rozycki reported that this case is
impossible.
Handle the impossible case by just returning instead of trying to
handle it. This makes static analysis simpler as it means nothing
needs to consider the impossible case after the return statement.
As the code no longer has to deal with this case remove FPE_FIXME from
the mips siginfo.h
Cc: "Maciej W. Rozycki" <macro@imgtec.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Link: http://lkml.kernel.org/r/20170718140651.15973-4-ebiederm@xmission.com
Ref: ea1b75cf91 ("signal/mips: Document a conflict with SI_USER with SIGFPE")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
While testing cpu hoptlug (cpu down and up in loops) on kernel 4.4, it was
observed that occasionally check for cpu online will fail in kernel/cpu.c,
_cpu_up:
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git/tree/kernel/cpu.c?h=v4.4.79#n485
518 /* Arch-specific enabling code. */
519 ret = __cpu_up(cpu, idle);
520
521 if (ret != 0)
522 goto out_notify;
523 BUG_ON(!cpu_online(cpu));
Reason is race between start_secondary and _cpu_up. cpu_callin_map is set
before cpu_online_mask. In __cpu_up, cpu_callin_map is waited for, but cpu
online mask is not, resulting in race in which secondary processor started
and set cpu_callin_map, but not yet set the online mask,resulting in above
BUG being hit.
Upstream differs in the area. cpu_online check is in bringup_wait_for_ap,
which is after cpu reached AP_ONLINE_IDLE,where secondary passed its start
function. Nonetheless, fix makes start_secondary safe and not depending on
other locks throughout the code. It protects as well against cpu_online
checks put in between sometimes in the future.
Fix this by moving completion after all flags are set.
Signed-off-by: Matija Glavinic Pecotic <matija.glavinic-pecotic.ext@nokia.com>
Cc: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16925/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
struct siginfo is a union and the kernel since 2.4 has been hiding a union
tag in the high 16bits of si_code using the values:
__SI_KILL
__SI_TIMER
__SI_POLL
__SI_FAULT
__SI_CHLD
__SI_RT
__SI_MESGQ
__SI_SYS
While this looks plausible on the surface, in practice this situation has
not worked well.
- Injected positive signals are not copied to user space properly
unless they have these magic high bits set.
- Injected positive signals are not reported properly by signalfd
unless they have these magic high bits set.
- These kernel internal values leaked to userspace via ptrace_peek_siginfo
- It was possible to inject these kernel internal values and cause the
the kernel to misbehave.
- Kernel developers got confused and expected these kernel internal values
in userspace in kernel self tests.
- Kernel developers got confused and set si_code to __SI_FAULT which
is SI_USER in userspace which causes userspace to think an ordinary user
sent the signal and that it was not kernel generated.
- The values make it impossible to reorganize the code to transform
siginfo_copy_to_user into a plain copy_to_user. As si_code must
be massaged before being passed to userspace.
So remove these kernel internal si codes and make the kernel code simpler
and more maintainable.
To replace these kernel internal magic si_codes introduce the helper
function siginfo_layout, that takes a signal number and an si_code and
computes which union member of siginfo is being used. Have
siginfo_layout return an enumeration so that gcc will have enough
information to warn if a switch statement does not handle all of union
members.
A couple of architectures have a messed up ABI that defines signal
specific duplications of SI_USER which causes more special cases in
siginfo_layout than I would like. The good news is only problem
architectures pay the cost.
Update all of the code that used the previous magic __SI_ values to
use the new SIL_ values and to call siginfo_layout to get those
values. Escept where not all of the cases are handled remove the
defaults in the switch statements so that if a new case is missed in
the future the lack will show up at compile time.
Modify the code that copies siginfo si_code to userspace to just copy
the value and not cast si_code to a short first. The high bits are no
longer used to hold a magic union member.
Fixup the siginfo header files to stop including the __SI_ values in
their constants and for the headers that were missing it to properly
update the number of si_codes for each signal type.
The fixes to copy_siginfo_from_user32 implementations has the
interesting property that several of them perviously should never have
worked as the __SI_ values they depended up where kernel internal.
With that dependency gone those implementations should work much
better.
The idea of not passing the __SI_ values out to userspace and then
not reinserting them has been tested with criu and criu worked without
changes.
Ref: 2.4.0-test1
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Setting si_code to __SI_FAULT results in a userspace seeing
an si_code of 0. This is the same si_code as SI_USER. Posix
and common sense requires that SI_USER not be a signal specific
si_code. As such this use of 0 for the si_code is a pretty
horribly broken ABI.
This use of of __SI_FAULT is only a decade old. Which compared
to the other pieces of kernel code that has made this mistake
is almost yesterday.
This is probably worth fixing but I don't know mips well enough
to know what si_code to would be the proper one to use.
Cc: Ralf Baechle <ralf@linux-mips.org>
Ref: 948a34cf39 ("[MIPS] Maintain si_code field properly for FP exceptions")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Pull MIPS updates from Ralf Baechle:
"Boston platform support:
- Document DT bindings
- Add CLK driver for board clocks
CM:
- Avoid per-core locking with CM3 & higher
- WARN on attempt to lock invalid VP, not BUG
CPS:
- Select CONFIG_SYS_SUPPORTS_SCHED_SMT for MIPSr6
- Prevent multi-core with dcache aliasing
- Handle cores not powering down more gracefully
- Handle spurious VP starts more gracefully
DSP:
- Add lwx & lhx missaligned access support
eBPF:
- Add MIPS support along with many supporting change to add the
required infrastructure
Generic arch code:
- Misc sysmips MIPS_ATOMIC_SET fixes
- Drop duplicate HAVE_SYSCALL_TRACEPOINTS
- Negate error syscall return in trace
- Correct forced syscall errors
- Traced negative syscalls should return -ENOSYS
- Allow samples/bpf/tracex5 to access syscall arguments for sane
traces
- Cleanup from old Kconfig options in defconfigs
- Fix PREF instruction usage by memcpy for MIPS R6
- Fix various special cases in the FPU eulation
- Fix some special cases in MIPS16e2 support
- Fix MIPS I ISA /proc/cpuinfo reporting
- Sort MIPS Kconfig alphabetically
- Fix minimum alignment requirement of IRQ stack as required by
ABI / GCC
- Fix special cases in the module loader
- Perform post-DMA cache flushes on systems with MAARs
- Probe the I6500 CPU
- Cleanup cmpxchg and add support for 1 and 2 byte operations
- Use queued read/write locks (qrwlock)
- Use queued spinlocks (qspinlock)
- Add CPU shared FTLB feature detection
- Handle tlbex-tlbp race condition
- Allow storing pgd in C0_CONTEXT for MIPSr6
- Use current_cpu_type() in m4kc_tlbp_war()
- Support Boston in the generic kernel
Generic platform:
- yamon-dt: Pull YAMON DT shim code out of SEAD-3 board
- yamon-dt: Support > 256MB of RAM
- yamon-dt: Use serial* rather than uart* aliases
- Abstract FDT fixup application
- Set RTC_ALWAYS_BCD to 0
- Add a MAINTAINERS entry
core kernel:
- qspinlock.c: include linux/prefetch.h
Loongson 3:
- Add support
Perf:
- Add I6500 support
SEAD-3:
- Remove GIC timer from DT
- Set interrupt-parent per-device, not at root node
- Fix GIC interrupt specifiers
SMP:
- Skip IPI setup if we only have a single CPU
VDSO:
- Make comment match reality
- Improvements to time code in VDSO"
* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (86 commits)
locking/qspinlock: Include linux/prefetch.h
MIPS: Fix MIPS I ISA /proc/cpuinfo reporting
MIPS: Fix minimum alignment requirement of IRQ stack
MIPS: generic: Support MIPS Boston development boards
MIPS: DTS: img: Don't attempt to build-in all .dtb files
clk: boston: Add a driver for MIPS Boston board clocks
dt-bindings: Document img,boston-clock binding
MIPS: Traced negative syscalls should return -ENOSYS
MIPS: Correct forced syscall errors
MIPS: Negate error syscall return in trace
MIPS: Drop duplicate HAVE_SYSCALL_TRACEPOINTS select
MIPS16e2: Provide feature overrides for non-MIPS16 systems
MIPS: MIPS16e2: Report ASE presence in /proc/cpuinfo
MIPS: MIPS16e2: Subdecode extended LWSP/SWSP instructions
MIPS: MIPS16e2: Identify ASE presence
MIPS: VDSO: Fix a mismatch between comment and preprocessor constant
MIPS: VDSO: Add implementation of gettimeofday() fallback
MIPS: VDSO: Add implementation of clock_gettime() fallback
MIPS: VDSO: Fix conversions in do_monotonic()/do_monotonic_coarse()
MIPS: Use current_cpu_type() in m4kc_tlbp_war()
...
Correct a commit 515a6393db ("MIPS: kernel: proc: Add MIPS R6 support
to /proc/cpuinfo") regression that caused MIPS I systems to show no ISA
levels supported in /proc/cpuinfo, e.g.:
system type : Digital DECstation 2100/3100
machine : Unknown
processor : 0
cpu model : R3000 V2.0 FPU V2.0
BogoMIPS : 10.69
wait instruction : no
microsecond timers : no
tlb_entries : 64
extra interrupt vector : no
hardware watchpoint : no
isa :
ASEs implemented :
shadow register sets : 1
kscratch registers : 0
package : 0
core : 0
VCED exceptions : not available
VCEI exceptions : not available
and similarly exclude `mips1' from the ISA list for any processors below
MIPSr1. This is because the condition to show `mips1' on has been made
`cpu_has_mips_r1' rather than newly-introduced `cpu_has_mips_1'. Use
the correct condition then.
Fixes: 515a6393db ("MIPS: kernel: proc: Add MIPS R6 support to /proc/cpuinfo")
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Reviewed-by: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: stable@vger.kernel.org # 3.19+
Patchwork: https://patchwork.linux-mips.org/patch/16758/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
If a negative system call number is used when system call tracing is
enabled, syscall_trace_enter() will return that negative system call
number without having written the return value and error flag into the
pt_regs.
The caller then treats it as a cancelled system call and assumes that
the return value and error flag are already written, leaving the
negative system call number in the return register ($v0), and the 4th
system call argument in the error register ($a3).
Add a special case to detect this at the end of syscall_trace_enter(),
to set the return value to error -ENOSYS when this happens.
Fixes: d218af7849 ("MIPS: scall: Always run the seccomp syscall filters")
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16653/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The sys_exit trace event takes a single return value for the system
call, which MIPS passes the value of the $v0 (result) register, however
MIPS returns positive error codes in $v0 with $a3 specifying that $v0
contains an error code. As a result erroring system calls are traced
returning positive error numbers that can't always be distinguished from
success.
Use regs_return_value() to negate the error code if $a3 is set.
Fixes: 1d7bf993e0 ("MIPS: ftrace: Add support for syscall tracepoints.")
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: linux-mips@linux-mips.org
Cc: <stable@vger.kernel.org> # 3.13+
Patchwork: https://patchwork.linux-mips.org/patch/16651/
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Only now that both feature determination and unaligned emulation is in
place add reporting to /proc/cpuinfo, so that the presence of "mips16e2"
there not only indicates our recognition of the hardware feature, but
correct unaligned emulation as well.
Signed-off-by: Maciej W. Rozycki <macro@imgtec.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16757/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Implement extended LWSP/SWSP instruction subdecoding for the purpose of
unaligned GP-relative memory access emulation.
With the introduction of the MIPS16e2 ASE[1] the previously must-be-zero
3-bit field at bits 7..5 of the extended encodings of the instructions
selected with the LWSP and SWSP major opcodes has become a `sel' field,
acting as an opcode extension for additional operations. In both cases
the `sel' value of 0 has retained the original operation, that is:
LW rx, offset(sp)
and:
SW rx, offset(sp)
for LWSP and SWSP respectively. In hardware predating the MIPS16e2 ASE
other values may or may not have been decoded, architecturally yielding
unpredictable results, and in our unaligned memory access emulation we
have treated the 3-bit field as a don't-care, that is effectively making
all the possible encodings of the field alias to the architecturally
defined encoding of 0.
For the non-zero values of the `sel' field the MIPS16e2 ASE has in
particular defined these GP-relative operations:
LW rx, offset(gp) # sel = 1
LH rx, offset(gp) # sel = 2
LHU rx, offset(gp) # sel = 4
and
SW rx, offset(gp) # sel = 1
SH rx, offset(gp) # sel = 2
for LWSP and SWSP respectively, which will trap with an Address Error
exception if the effective address calculated is not naturally-aligned
for the operation requested. These operations have been selected for
unaligned access emulation, for consistency with the corresponding
regular MIPS and microMIPS operations.
For other non-zero values of the `sel' field the MIPS16e2 ASE has
defined further operations, which however either never trap with an
Address Error exception, such as LWL or GP-relative SB, or are not
supposed to be emulated, such as LL or SC. These operations have been
selected to exclude from unaligned access emulation, should an Address
Error exception ever happen with them.
Subdecode the `sel' field in unaligned access emulation then for the
extended encodings of the instructions selected with the LWSP and SWSP
major opcodes, whenever support for the MIPS16e2 ASE has been detected
in hardware, and either emulate the operation requested or send SIGBUS
to the originating process, according to the selection described above.
For hardware implementing the MIPS16 ASE, however lacking MIPS16e2 ASE
support retain the original interpretation of the `sel' field.
The effects of this change are illustrated with the following user
program:
$ cat mips16e2-test.c
#include <inttypes.h>
#include <stdio.h>
int main(void)
{
int64_t scratch[16] = { 0 };
int32_t *tmp0, *tmp1, *tmp2;
int i;
scratch[0] = 0xc8c7c6c5c4c3c2c1;
scratch[1] = 0xd0cfcecdcccbcac9;
asm volatile(
"move %0, $sp\n\t"
"move %1, $gp\n\t"
"move $sp, %4\n\t"
"addiu %2, %4, 8\n\t"
"move $gp, %2\n\t"
"lw %2, 2($sp)\n\t"
"sw %2, 16(%4)\n\t"
"lw %2, 2($gp)\n\t"
"sw %2, 24(%4)\n\t"
"lw %2, 1($sp)\n\t"
"sw %2, 32(%4)\n\t"
"lh %2, 1($gp)\n\t"
"sw %2, 40(%4)\n\t"
"lw %2, 3($sp)\n\t"
"sw %2, 48(%4)\n\t"
"lhu %2, 3($gp)\n\t"
"sw %2, 56(%4)\n\t"
"lw %2, 0(%4)\n\t"
"sw %2, 66($sp)\n\t"
"lw %2, 8(%4)\n\t"
"sw %2, 82($gp)\n\t"
"lw %2, 0(%4)\n\t"
"sw %2, 97($sp)\n\t"
"lw %2, 8(%4)\n\t"
"sh %2, 113($gp)\n\t"
"move $gp, %1\n\t"
"move $sp, %0"
: "=&d" (tmp0), "=&d" (tmp1), "=&d" (tmp2), "=m" (scratch)
: "d" (scratch));
for (i = 0; i < sizeof(scratch) / sizeof(*scratch); i += 2)
printf("%016" PRIx64 "\t%016" PRIx64 "\n",
scratch[i], scratch[i + 1]);
return 0;
}
$
to be compiled with:
$ gcc -mips16 -mips32r2 -Wa,-mmips16e2 -o mips16e2-test mips16e2-test.c
$
With 74Kf hardware, which does not implement the MIPS16e2 ASE, this
program produces the following output:
$ ./mips16e2-test
c8c7c6c5c4c3c2c1 d0cfcecdcccbcac9
00000000c6c5c4c3 00000000c6c5c4c3
00000000c5c4c3c2 00000000c5c4c3c2
00000000c7c6c5c4 00000000c7c6c5c4
0000c4c3c2c10000 0000000000000000
0000cccbcac90000 0000000000000000
000000c4c3c2c100 0000000000000000
000000cccbcac900 0000000000000000
$
regardless of whether the change has been applied or not.
With the change not applied and interAptive MR2 hardware[2], which does
implement the MIPS16e2 ASE, it produces the following output:
$ ./mips16e2-test
c8c7c6c5c4c3c2c1 d0cfcecdcccbcac9
00000000c6c5c4c3 00000000cecdcccb
00000000c5c4c3c2 00000000cdcccbca
00000000c7c6c5c4 00000000cfcecdcc
0000c4c3c2c10000 0000000000000000
0000000000000000 0000cccbcac90000
000000c4c3c2c100 0000000000000000
0000000000000000 000000cccbcac900
$
which shows that for GP-relative operations the correct trapping address
calculated from $gp has been obtained from the CP0 BadVAddr register and
so has data from the source operand, however masking and extension has
not been applied for halfword operations.
With the change applied and interAptive MR2 hardware the program
produces the following output:
$ ./mips16e2-test
c8c7c6c5c4c3c2c1 d0cfcecdcccbcac9
00000000c6c5c4c3 00000000cecdcccb
00000000c5c4c3c2 00000000ffffcbca
00000000c7c6c5c4 000000000000cdcc
0000c4c3c2c10000 0000000000000000
0000000000000000 0000cccbcac90000
000000c4c3c2c100 0000000000000000
0000000000000000 0000000000cac900
$
as expected.
References:
[1] "MIPS32 Architecture for Programmers: MIPS16e2 Application-Specific
Extension Technical Reference Manual", Imagination Technologies
Ltd., Document Number: MD01172, Revision 01.00, April 26, 2016
[2] "MIPS32 interAptiv Multiprocessing System Software User's Manual",
Imagination Technologies Ltd., Document Number: MD00904, Revision
02.01, June 15, 2016, Chapter 24 "MIPS16e Application-Specific
Extension to the MIPS32 Instruction Set", pp. 871-883
Signed-off-by: Maciej W. Rozycki <macro@imgtec.com>
Reviewed-by: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16095/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Identify the presence of the MIPS16e2 ASE as per the architecture
specification[1], by checking for CP0 Config5.CA2 bit being 1[2].
References:
[1] "MIPS32 Architecture for Programmers: MIPS16e2 Application-Specific
Extension Technical Reference Manual", Imagination Technologies
Ltd., Document Number: MD01172, Revision 01.00, April 26, 2016,
Section 1.2 "Software Detection of the ASE", p. 5
[2] "MIPS32 interAptiv Multiprocessing System Software User's Manual",
Imagination Technologies Ltd., Document Number: MD00904, Revision
02.01, June 15, 2016, Section 2.2.1.6 "Device Configuration 5 --
Config5 (CP0 Register 16, Select 5)", pp. 71-72
Signed-off-by: Maciej W. Rozycki <macro@imgtec.com>
Reviewed-by: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16094/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Pull SMP hotplug updates from Thomas Gleixner:
"This update is primarily a cleanup of the CPU hotplug locking code.
The hotplug locking mechanism is an open coded RWSEM, which allows
recursive locking. The main problem with that is the recursive nature
as it evades the full lockdep coverage and hides potential deadlocks.
The rework replaces the open coded RWSEM with a percpu RWSEM and
establishes full lockdep coverage that way.
The bulk of the changes fix up recursive locking issues and address
the now fully reported potential deadlocks all over the place. Some of
these deadlocks have been observed in the RT tree, but on mainline the
probability was low enough to hide them away."
* 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (37 commits)
cpu/hotplug: Constify attribute_group structures
powerpc: Only obtain cpu_hotplug_lock if called by rtasd
ARM/hw_breakpoint: Fix possible recursive locking for arch_hw_breakpoint_init
cpu/hotplug: Remove unused check_for_tasks() function
perf/core: Don't release cred_guard_mutex if not taken
cpuhotplug: Link lock stacks for hotplug callbacks
acpi/processor: Prevent cpu hotplug deadlock
sched: Provide is_percpu_thread() helper
cpu/hotplug: Convert hotplug locking to percpu rwsem
s390: Prevent hotplug rwsem recursion
arm: Prevent hotplug rwsem recursion
arm64: Prevent cpu hotplug rwsem recursion
kprobes: Cure hotplug lock ordering issues
jump_label: Reorder hotplug lock and jump_label_lock
perf/tracing/cpuhotplug: Fix locking order
ACPI/processor: Use cpu_hotplug_disable() instead of get_online_cpus()
PCI: Replace the racy recursion prevention
PCI: Use cpu_hotplug_disable() instead of get_online_cpus()
perf/x86/intel: Drop get_online_cpus() in intel_snb_check_microcode()
x86/perf: Drop EXPORT of perf_check_microcode
...
Since commit 81a76d7119 ("MIPS: Avoid using unwind_stack() with
usermode") show_backtrace() invokes the raw backtracer when
cp0_status & ST0_KSU indicates user mode to fix issues on EVA kernels
where user and kernel address spaces overlap.
However this is used by show_stack() which creates its own pt_regs on
the stack and leaves cp0_status uninitialised in most of the code paths.
This results in the non deterministic use of the raw back tracer
depending on the previous stack content.
show_stack() deals exclusively with kernel mode stacks anyway, so
explicitly initialise regs.cp0_status to KSU_KERNEL (i.e. 0) to ensure
we get a useful backtrace.
Fixes: 81a76d7119 ("MIPS: Avoid using unwind_stack() with usermode")
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: <stable@vger.kernel.org> # 3.15+
Patchwork: https://patchwork.linux-mips.org/patch/16656/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
When the scheduler sets TIF_NEED_RESCHED & we call into the scheduler
from arch/mips/kernel/entry.S we disable interrupts. This is true
regardless of whether we reach work_resched from syscall_exit_work,
resume_userspace or by looping after calling schedule(). Although we
disable interrupts in these paths we don't call trace_hardirqs_off()
before calling into C code which may acquire locks, and we therefore
leave lockdep with an inconsistent view of whether interrupts are
disabled or not when CONFIG_PROVE_LOCKING & CONFIG_DEBUG_LOCKDEP are
both enabled.
Without tracing this interrupt state lockdep will print warnings such
as the following once a task returns from a syscall via
syscall_exit_partial with TIF_NEED_RESCHED set:
[ 49.927678] ------------[ cut here ]------------
[ 49.934445] WARNING: CPU: 0 PID: 1 at kernel/locking/lockdep.c:3687 check_flags.part.41+0x1dc/0x1e8
[ 49.946031] DEBUG_LOCKS_WARN_ON(current->hardirqs_enabled)
[ 49.946355] CPU: 0 PID: 1 Comm: init Not tainted 4.10.0-00439-gc9fd5d362289-dirty #197
[ 49.963505] Stack : 0000000000000000 ffffffff81bb5d6a 0000000000000006 ffffffff801ce9c4
[ 49.974431] 0000000000000000 0000000000000000 0000000000000000 000000000000004a
[ 49.985300] ffffffff80b7e487 ffffffff80a24498 a8000000ff160000 ffffffff80ede8b8
[ 49.996194] 0000000000000001 0000000000000000 0000000000000000 0000000077c8030c
[ 50.007063] 000000007fd8a510 ffffffff801cd45c 0000000000000000 a8000000ff127c88
[ 50.017945] 0000000000000000 ffffffff801cf928 0000000000000001 ffffffff80a24498
[ 50.028827] 0000000000000000 0000000000000001 0000000000000000 0000000000000000
[ 50.039688] 0000000000000000 a8000000ff127bd0 0000000000000000 ffffffff805509bc
[ 50.050575] 00000000140084e0 0000000000000000 0000000000000000 0000000000040a00
[ 50.061448] 0000000000000000 ffffffff8010e1b0 0000000000000000 ffffffff805509bc
[ 50.072327] ...
[ 50.076087] Call Trace:
[ 50.079869] [<ffffffff8010e1b0>] show_stack+0x80/0xa8
[ 50.086577] [<ffffffff805509bc>] dump_stack+0x10c/0x190
[ 50.093498] [<ffffffff8015dde0>] __warn+0xf0/0x108
[ 50.099889] [<ffffffff8015de34>] warn_slowpath_fmt+0x3c/0x48
[ 50.107241] [<ffffffff801c15b4>] check_flags.part.41+0x1dc/0x1e8
[ 50.114961] [<ffffffff801c239c>] lock_is_held_type+0x8c/0xb0
[ 50.122291] [<ffffffff809461b8>] __schedule+0x8c0/0x10f8
[ 50.129221] [<ffffffff80946a60>] schedule+0x30/0x98
[ 50.135659] [<ffffffff80106278>] work_resched+0x8/0x34
[ 50.142397] ---[ end trace 0cb4f6ef5b99fe21 ]---
[ 50.148405] possible reason: unannotated irqs-off.
[ 50.154600] irq event stamp: 400463
[ 50.159566] hardirqs last enabled at (400463): [<ffffffff8094edc8>] _raw_spin_unlock_irqrestore+0x40/0xa8
[ 50.171981] hardirqs last disabled at (400462): [<ffffffff8094eb98>] _raw_spin_lock_irqsave+0x30/0xb0
[ 50.183897] softirqs last enabled at (400450): [<ffffffff8016580c>] __do_softirq+0x4ac/0x6a8
[ 50.195015] softirqs last disabled at (400425): [<ffffffff80165e78>] irq_exit+0x110/0x128
Fix this by using the TRACE_IRQS_OFF macro to call trace_hardirqs_off()
when CONFIG_TRACE_IRQFLAGS is enabled. This is done before invoking
schedule() following the work_resched label because:
1) Interrupts are disabled regardless of the path we take to reach
work_resched() & schedule().
2) Performing the tracing here avoids the need to do it in paths which
disable interrupts but don't call out to C code before hitting a
path which uses the RESTORE_SOME macro that will call
trace_hardirqs_on() or trace_hardirqs_off() as appropriate.
We call trace_hardirqs_on() using the TRACE_IRQS_ON macro before calling
syscall_trace_leave() for similar reasons, ensuring that lockdep has a
consistent view of state after we re-enable interrupts.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Cc: linux-mips@linux-mips.org
Cc: stable <stable@vger.kernel.org>
Patchwork: https://patchwork.linux-mips.org/patch/15385/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
We allocate memory for a ready_count variable per-CPU, which is accessed
via a cached non-coherent TLB mapping to perform synchronisation between
threads within the core using LL/SC instructions. In order to ensure
that the variable is contained within its own data cache line we
allocate 2 lines worth of memory & align the resulting pointer to a line
boundary. This is however unnecessary, since kmalloc is guaranteed to
return memory which is at least cache-line aligned (see
ARCH_DMA_MINALIGN). Stop the redundant manual alignment.
Besides cleaning up the code & avoiding needless work, this has the side
effect of avoiding an arithmetic error found by Bryan on 64 bit systems
due to the 32 bit size of the former dlinesz. This led the ready_count
variable to have its upper 32b cleared erroneously for MIPS64 kernels,
causing problems when ready_count was later used on MIPS64 via cpuidle.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Fixes: 3179d37ee1 ("MIPS: pm-cps: add PM state entry code for CPS systems")
Reported-by: Bryan O'Donoghue <bryan.odonoghue@imgtec.com>
Reviewed-by: Bryan O'Donoghue <bryan.odonoghue@imgtec.com>
Tested-by: Bryan O'Donoghue <bryan.odonoghue@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: stable <stable@vger.kernel.org> # v3.16+
Patchwork: https://patchwork.linux-mips.org/patch/15383/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Some systems share FTLB RAMs or entries between sibling CPUs (ie.
hardware threads, or VP(E)s, within a core). These properties require
kernel handling in various places. As a start this patch introduces
cpu_has_shared_ftlb_ram & cpu_has_shared_ftlb_entries feature macros
which we set appropriately for I6400 & I6500 CPUs. Further patches will
make use of these macros as appropriate.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16202/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
On pre-r6 systems with the MT ASE the CPS SMP code included checks to
halt the VPE running mips_cps_boot_vpes() if its bit in the struct
core_boot_config vpe_mask field is clear. This was largely done in order
to allow us to start arbitrary VPEs within a core despite the fact that
hardware is typically configured to run only VPE0 after powering up a
core. VPE0 would start the desired other VPEs, halt itself, and the fact
that VPE0 started would be largely hidden & irrelevant.
In MIPSr6 multithreading we have control over which VPs start executing
when a core powers up via the cores CPC registers accessed remotely
through the redirect block. For this reason the MIPSr6 multithreading
path in mips_cps_boot_vpes() hasn't bothered up until now to handle
halting the VP running it.
However it is possible to power up cores entirely in hardware by using a
pwr_up pin associated with the core. Unfortunately some systems wire
this pin to a logic 1, which means that it is possible for a core to
power up at a point that software doesn't expect. The result is that we
generally go execute the kernel on a CPU that ought not to be running &
the results can be unpredictable.
Handle this case by stopping VPs that we don't expect to be running in
mips_cps_boot_vpes() - with this change even if a core powers up it will
do nothing useful & all VPs within it will stop running before they
proceed to run general kernel code & do any damage. Ideally we would
produce some sort of warning here, but given the stage of core bringup
this happens at that would be non-trivial. We also will only hit this if
a core starts up after being offlined via hotplug, and when that happens
we will already produce a warning that the CPU didn't power down in
cps_cpu_die() which seems sufficient.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16198/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
If we get into a state where a core that ought to power down isn't doing
so then the current result is that another CPU gets stuck inside
cps_cpu_die() waiting for CPU that ought to be powering down to do so.
The best case scenario is that we then trigger RCU stall messages or
lockup messages, but neither makes it particularly clear what's
happening.
Handle this more gracefully by introducing a timeout beyond which we
warn the user that the core didn't power down & stop waiting for it.
This at least allows the CPU running cps_cpu_die() to continue normally,
and hopefully presuming the CPU that powered back up is doing nothing
harmful the system will continue functioning as normal.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16197/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Systems using the MIPS Coherence Manager (CM) cannot support multi-core
SMP with dcache aliasing. This is because CPU caches are VIPT, but
interventions in CM-based systems provide only the physical address to
remote caches. This means that interventions may behave incorrectly in
the presence of an aliasing dcache, since the physical address used
when handling an intervention may lead to operation on an aliased cache
line rather than the correct line.
Prevent us from running into this issue by refusing to boot secondary
cores in systems where dcache aliasing may occur.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16196/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Rather than using BUG_ON in the case of an invalid attempt to lock
access to a non-zero VP on a pre-CM3 system, use WARN_ON so that we have
even the slightest chance of recovery.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16194/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
CM3 provides a GCR_CL_OTHER register per VP, rather than only per core.
This means that we don't need to prevent other VPs within a core from
racing with code that makes use of the core-other register region.
Reduce locking overhead by demoting the per-core spinlock providing
protection for CM2.5 & lower to a per-CPU/per-VP spinlock for CM3 &
higher.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16193/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
If we're running on a system with only 1 possible CPU then it makes no
sense to reserve or initialise IPIs since we'll never use them. Avoid
doing so.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16192/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Reduce the log level for branch emulation error messages issued before
sending SIGILL by `__compute_return_epc_for_insn' as these are triggered
by user software and are not an event that would normally require any
attention. The same signal sent from elsewhere does not actually leave
any trace in the kernel log at all.
Signed-off-by: Maciej W. Rozycki <macro@imgtec.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16402/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This is a user-visible message, so we want it to be spelled correctly.
Fixes: 5f9f41c474 ("MIPS: kernel: Prepare the JR instruction for emulation on MIPS R6")
Signed-off-by: Maciej W. Rozycki <macro@imgtec.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: stable@vger.kernel.org # 3.19+
Patchwork: https://patchwork.linux-mips.org/patch/16400/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Fix:
* commit 8467ca0122 ("MIPS: Emulate the new MIPS R6 branch compact
(BC) instruction"),
* commit 84fef63012 ("MIPS: Emulate the new MIPS R6 BALC
instruction"),
* commit 69b9a2fd05 ("MIPS: Emulate the new MIPS R6 BEQZC and JIC
instructions"),
* commit 28d6f93d20 ("MIPS: Emulate the new MIPS R6 BNEZC and JIALC
instructions"),
* commit c893ce38b2 ("MIPS: Emulate the new MIPS R6 BOVC, BEQC and
BEQZALC instructions")
and send SIGILL rather than returning -SIGILL for R6 branch and jump
instructions. Returning -SIGILL is never correct as the API defines
this function's result upon error to be -EFAULT and a signal actually
issued.
Fixes: 8467ca0122 ("MIPS: Emulate the new MIPS R6 branch compact (BC) instruction")
Fixes: 84fef63012 ("MIPS: Emulate the new MIPS R6 BALC instruction")
Fixes: 69b9a2fd05 ("MIPS: Emulate the new MIPS R6 BEQZC and JIC instructions")
Fixes: 28d6f93d20 ("MIPS: Emulate the new MIPS R6 BNEZC and JIALC instructions")
Fixes: c893ce38b2 ("MIPS: Emulate the new MIPS R6 BOVC, BEQC and BEQZALC instructions")
Signed-off-by: Maciej W. Rozycki <macro@imgtec.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: stable@vger.kernel.org # 3.19+
Patchwork: https://patchwork.linux-mips.org/patch/16399/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Fix commit 319824eabc ("MIPS: kernel: branch: Do not emulate the
branch likelies on MIPS R6") and also send SIGILL rather than returning
-SIGILL for BLTZAL, BLTZALL, BGEZAL and BGEZALL instruction encodings no
longer supported in R6, except where emulated. Returning -SIGILL is
never correct as the API defines this function's result upon error to be
-EFAULT and a signal actually issued.
Fixes: 319824eabc ("MIPS: kernel: branch: Do not emulate the branch likelies on MIPS R6")
Signed-off-by: Maciej W. Rozycki <macro@imgtec.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: stable@vger.kernel.org # 3.19+
Patchwork: https://patchwork.linux-mips.org/patch/16398/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Use the more accurate `sigill_r2r6' name for the label used in the case
of sending SIGILL in the absence of the instruction emulator for an
earlier ISA level instruction that has been removed as from the R6 ISA,
so that the `sigill_r6' name is freed for the situation where an R6
instruction is not supposed to be interpreted, because the executing
processor does not support the R6 ISA.
Signed-off-by: Maciej W. Rozycki <macro@imgtec.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: stable@vger.kernel.org # 3.19+
Patchwork: https://patchwork.linux-mips.org/patch/16397/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Fix commit e50c0a8fa6 ("Support the MIPS32 / MIPS64 DSP ASE.") and
send SIGILL rather than SIGBUS whenever an unimplemented BPOSGE32 DSP
ASE instruction has been encountered in `__compute_return_epc_for_insn'
as our Reserved Instruction exception handler would in response to an
attempt to actually execute the instruction. Sending SIGBUS only makes
sense for the unaligned PC case, since moved to `__compute_return_epc'.
Adjust function documentation accordingly, correct formatting and use
`pr_info' rather than `printk' as the other exit path already does.
Fixes: e50c0a8fa6 ("Support the MIPS32 / MIPS64 DSP ASE.")
Signed-off-by: Maciej W. Rozycki <macro@imgtec.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: stable@vger.kernel.org # 2.6.14+
Patchwork: https://patchwork.linux-mips.org/patch/16396/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Complement commit fb6883e580 ("MIPS: microMIPS: Support handling of
delay slots.") and actually decode the regular MIPS JALX major
instruction opcode, the handling of which has been added with the said
commit for EPC calculation in `__compute_return_epc_for_insn'.
Fixes: fb6883e580 ("MIPS: microMIPS: Support handling of delay slots.")
Signed-off-by: Maciej W. Rozycki <macro@imgtec.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: stable@vger.kernel.org # 3.9+
Patchwork: https://patchwork.linux-mips.org/patch/16394/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Implement support for 1 & 2 byte cmpxchg() using read-modify-write atop
a 4 byte cmpxchg(). This allows us to support these atomic operations
despite the MIPS ISA only providing 4 & 8 byte atomic operations.
This is required in order to support queued rwlocks (qrwlock) in a later
patch, since these make use of a 1 byte cmpxchg() in their slow path.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16355/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Implement 1 & 2 byte xchg() using read-modify-write atop a 4 byte
cmpxchg(). This allows us to support these atomic operations despite the
MIPS ISA only providing for 4 & 8 byte atomic operations.
This is required in order to support queued spinlocks (qspinlock) in a
later patch, since these make use of a 2 byte xchg() in their slow path.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16354/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Implement support for parsing 'memmap' kernel command line parameter.
This patch covers parsing of the following two formats for 'memmap'
parameter values:
- nn[KMG]@ss[KMG]
- nn[KMG]$ss[KMG]
([KMG] = K M or G (kilo, mega, giga))
These two allowed formats for parameter value are already documented
in file kernel-parameters.txt in Documentation/admin-guide folder.
Some architectures already support them, but Mips did not prior to
this patch.
Excerpt from Documentation/admin-guide/kernel-parameters.txt:
memmap=nn[KMG]@ss[KMG]
[KNL] Force usage of a specific region of memory.
Region of memory to be used is from ss to ss+nn.
memmap=nn[KMG]$ss[KMG]
Mark specific memory as reserved.
Region of memory to be reserved is from ss to ss+nn.
Example: Exclude memory from 0x18690000-0x1869ffff
memmap=64K$0x18690000
or
memmap=0x10000$0x18690000
There is no need to update this documentation file with respect to
this patch.
Signed-off-by: Miodrag Dinic <miodrag.dinic@imgtec.com>
Signed-off-by: Goran Ferenc <goran.ferenc@imgtec.com>
Signed-off-by: Aleksandar Markovic <aleksandar.markovic@imgtec.com>
Cc: James.Hogan@imgtec.com
Cc: Paul.Burton@imgtec.com
Cc: Raghu.Gandham@imgtec.com
Cc: Leonid.Yegoshin@imgtec.com
Cc: Douglas.Leung@imgtec.com
Cc: Petar.Jovanovic@imgtec.com
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16508/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Adjust the atomic loop in the MIPS_ATOMIC_SET operation of the sysmips
system call to branch straight back to the linked load rather than
jumping via a different subsection (whose purpose remains a mystery to
me).
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16150/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
EVA linked loads (LLE) and conditional stores (SCE) should be used on
EVA kernels for the MIPS_ATOMIC_SET operation of the sysmips system
call, or else the atomic set will apply to the kernel view of the
virtual address space (potentially unmapped on EVA kernels) rather than
the user view (TLB mapped).
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: <stable@vger.kernel.org> # 3.15.x-
Patchwork: https://patchwork.linux-mips.org/patch/16151/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The MIPS sysmips system call handler may return directly from the
MIPS_ATOMIC_SET case (mips_atomic_set()) to syscall_exit. This path
restores the static (callee saved) registers, however they won't have
been saved on entry to the system call.
Use the save_static_function() macro to create a __sys_sysmips wrapper
function which saves the static registers before calling sys_sysmips, so
that the correct static register state is restored by syscall_exit.
Fixes: f1e39a4a61 ("MIPS: Rewrite sysmips(MIPS_ATOMIC_SET, ...) in C with inline assembler")
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: stable@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/16149/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The inline asm retry check in the MIPS_ATOMIC_SET operation of the
sysmips system call has been backwards since commit f1e39a4a61 ("MIPS:
Rewrite sysmips(MIPS_ATOMIC_SET, ...) in C with inline assembler")
merged in v2.6.32, resulting in the non R10000_LLSC_WAR case retrying
until the operation was inatomic, before returning the new value that
was probably just written multiple times instead of the old value.
Invert the branch condition to fix that particular issue.
Fixes: f1e39a4a61 ("MIPS: Rewrite sysmips(MIPS_ATOMIC_SET, ...) in C with inline assembler")
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: stable@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/16148/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Add a definition of the perf registers for the new I6500 core.
Since I6500 has the same event definitions as I6400, re-use the existing
i6400 map structures by renaming them to a slightly more generic
'i6x00_***_map'.
Signed-off-by: Marcin Nowakowski <marcin.nowakowski@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16362/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Introduce the I6500 PRID & probe it just the same way as I6400. The MIPS
I6500 is the latest in Imagination Technologies' I-Class range of CPUs,
with a focus on scalability & heterogeneity. It introduces the notion of
multiple clusters to the MIPS Coherent Processing System, allowing for a
far higher total number of cores & threads in a system when compared
with its predecessors. Clusters don't need to be identical, and may
contain differing numbers of cores & IOCUs, or cores with differing
properties.
This patch alone adds the basic support for booting Linux on an I6500
CPU without support for any of its new functionality, for which support
will be introduced in further patches.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16190/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
KProbes of __seccomp_filter() are not very useful without access to
the syscall arguments.
Do what x86 does, and populate a struct seccomp_data to be passed to
__secure_computing(). This allows samples/bpf/tracex5 to extract a
sensible trace.
Signed-off-by: David Daney <david.daney@cavium.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: netdev@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16368/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The module load code has previously had entirely separate
implementations for rel & rela style relocs, which unnecessarily
duplicates a whole lot of code. Unify the implementations of both types
of reloc, sharing the bulk of the code.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/15832/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
If we hit an error whilst processing a reloc then we would return early
from apply_relocate & potentially not free entries in r_mips_hi16_list,
thereby leaking memory. Fix this by ensuring that we always run the code
to free r_mipps_hi16_list when errors occur.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Fixes: 861667dc82 ("MIPS: Fix race condition in module relocation code.")
Fixes: 04211a5746 ("MIPS: Bail on unsupported module relocs")
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/15831/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
In this sequence the 'move' is assumed in the delay slot of the 'beq',
but head.S is in reorder mode and the former gets pushed one 'nop'
farther by the assembler.
The corrected behavior made booting with an UHI supplied dtb erratic.
Fixes: 15f37e1588 ("MIPS: store the appended dtb address in a variable")
Signed-off-by: Karl Beldan <karl.beldan+oss@gmail.com>
Reviewed-by: James Hogan <james.hogan@imgtec.com>
Cc: Jonas Gorski <jogo@openwrt.org>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Cc: stable@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/16614/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The code handling the pop76 opcode (ie. bnezc & jialc instructions) in
__compute_return_epc_for_insn() needs to set the value of $31 in the
jialc case, which is encoded with rs = 0. However its check to
differentiate bnezc (rs != 0) from jialc (rs = 0) was unfortunately
backwards, meaning that if we emulate a bnezc instruction we clobber $31
& if we emulate a jialc instruction it actually behaves like a jic
instruction.
Fix this by inverting the check of rs to match the way the instructions
are actually encoded.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Fixes: 28d6f93d20 ("MIPS: Emulate the new MIPS R6 BNEZC and JIALC instructions")
Cc: stable <stable@vger.kernel.org> # v4.0+
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16178/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Since introduction of tracing for init functions the in_kernel_space()
check is no longer correct, as it ignores the init sections. As a
result, when probes are inserted (and disabled) in the init functions,
a branch instruction is inserted instead of a nop, which is likely to
result in random crashes during boot.
Remove the MIPS-specific in_kernel_space() method and replace it with a
generic core_kernel_text() that also checks for init sections during
system boot stage.
Fixes: 42c269c88d ("ftrace: Allow for function tracing to record init functions on boot up")
Signed-off-by: Marcin Nowakowski <marcin.nowakowski@imgtec.com>
Tested-by: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16092/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
All performance counters on I6400 (odd and even) are capable of counting
any of the available events, so drop current logic of using the extra
bit to determine which counter to use.
Signed-off-by: Marcin Nowakowski <marcin.nowakowski@imgtec.com>
Fixes: 4e88a86213 ("MIPS: Add cases for CPU_I6400")
Fixes: fd716fca10 ("MIPS: perf: Fix I6400 event numbers")
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/15991/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Matt Redfearn