linux/arch
Athira Rajeev 28aaed966e powerpc/perf: Fix power_pmu_disable to call clear_pmi_irq_pending only if PMI is pending
[ Upstream commit fb6433b48a ]

Running selftest with CONFIG_PPC_IRQ_SOFT_MASK_DEBUG enabled in kernel
triggered below warning:

[  172.851380] ------------[ cut here ]------------
[  172.851391] WARNING: CPU: 8 PID: 2901 at arch/powerpc/include/asm/hw_irq.h:246 power_pmu_disable+0x270/0x280
[  172.851402] Modules linked in: dm_mod bonding nft_ct nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 ip_set nf_tables rfkill nfnetlink sunrpc xfs libcrc32c pseries_rng xts vmx_crypto uio_pdrv_genirq uio sch_fq_codel ip_tables ext4 mbcache jbd2 sd_mod t10_pi sg ibmvscsi ibmveth scsi_transport_srp fuse
[  172.851442] CPU: 8 PID: 2901 Comm: lost_exception_ Not tainted 5.16.0-rc5-03218-g798527287598 #2
[  172.851451] NIP:  c00000000013d600 LR: c00000000013d5a4 CTR: c00000000013b180
[  172.851458] REGS: c000000017687860 TRAP: 0700   Not tainted  (5.16.0-rc5-03218-g798527287598)
[  172.851465] MSR:  8000000000029033 <SF,EE,ME,IR,DR,RI,LE>  CR: 48004884  XER: 20040000
[  172.851482] CFAR: c00000000013d5b4 IRQMASK: 1
[  172.851482] GPR00: c00000000013d5a4 c000000017687b00 c000000002a10600 0000000000000004
[  172.851482] GPR04: 0000000082004000 c0000008ba08f0a8 0000000000000000 00000008b7ed0000
[  172.851482] GPR08: 00000000446194f6 0000000000008000 c00000000013b118 c000000000d58e68
[  172.851482] GPR12: c00000000013d390 c00000001ec54a80 0000000000000000 0000000000000000
[  172.851482] GPR16: 0000000000000000 0000000000000000 c000000015d5c708 c0000000025396d0
[  172.851482] GPR20: 0000000000000000 0000000000000000 c00000000a3bbf40 0000000000000003
[  172.851482] GPR24: 0000000000000000 c0000008ba097400 c0000000161e0d00 c00000000a3bb600
[  172.851482] GPR28: c000000015d5c700 0000000000000001 0000000082384090 c0000008ba0020d8
[  172.851549] NIP [c00000000013d600] power_pmu_disable+0x270/0x280
[  172.851557] LR [c00000000013d5a4] power_pmu_disable+0x214/0x280
[  172.851565] Call Trace:
[  172.851568] [c000000017687b00] [c00000000013d5a4] power_pmu_disable+0x214/0x280 (unreliable)
[  172.851579] [c000000017687b40] [c0000000003403ac] perf_pmu_disable+0x4c/0x60
[  172.851588] [c000000017687b60] [c0000000003445e4] __perf_event_task_sched_out+0x1d4/0x660
[  172.851596] [c000000017687c50] [c000000000d1175c] __schedule+0xbcc/0x12a0
[  172.851602] [c000000017687d60] [c000000000d11ea8] schedule+0x78/0x140
[  172.851608] [c000000017687d90] [c0000000001a8080] sys_sched_yield+0x20/0x40
[  172.851615] [c000000017687db0] [c0000000000334dc] system_call_exception+0x18c/0x380
[  172.851622] [c000000017687e10] [c00000000000c74c] system_call_common+0xec/0x268

The warning indicates that MSR_EE being set(interrupt enabled) when
there was an overflown PMC detected. This could happen in
power_pmu_disable since it runs under interrupt soft disable
condition ( local_irq_save ) and not with interrupts hard disabled.
commit 2c9ac51b85 ("powerpc/perf: Fix PMU callbacks to clear
pending PMI before resetting an overflown PMC") intended to clear
PMI pending bit in Paca when disabling the PMU. It could happen
that PMC gets overflown while code is in power_pmu_disable
callback function. Hence add a check to see if PMI pending bit
is set in Paca before clearing it via clear_pmi_pending.

Fixes: 2c9ac51b85 ("powerpc/perf: Fix PMU callbacks to clear pending PMI before resetting an overflown PMC")
Reported-by: Sachin Sant <sachinp@linux.ibm.com>
Signed-off-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Tested-by: Sachin Sant <sachinp@linux.ibm.com>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220122033429.25395-1-atrajeev@linux.vnet.ibm.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-02-01 17:27:12 +01:00
..
alpha alpha: enable GENERIC_PCI_IOMAP unconditionally 2021-09-19 10:37:00 -07:00
arc signal: Replace force_sigsegv(SIGSEGV) with force_fatal_sig(SIGSEGV) 2021-11-25 09:49:06 +01:00
arm ARM: 9170/1: fix panic when kasan and kprobe are enabled 2022-02-01 17:27:07 +01:00
arm64 KVM: arm64: pkvm: Use the mm_ops indirection for cache maintenance 2022-02-01 17:27:09 +01:00
csky perf: Protect perf_guest_cbs with RCU 2022-01-20 09:13:14 +01:00
h8300 Merge branch 'akpm' (patches from Andrew) 2021-09-08 12:55:35 -07:00
hexagon hexagon: clean up timer-regs.h 2021-11-25 09:48:42 +01:00
ia64 PCI/sysfs: Find shadow ROM before static attribute initialization 2022-02-01 17:27:05 +01:00
m68k signal: Replace force_fatal_sig with force_exit_sig when in doubt 2021-11-25 09:49:07 +01:00
microblaze Microblaze patches for 5.15-rc1 2021-09-08 16:02:13 -07:00
mips PCI/sysfs: Find shadow ROM before static attribute initialization 2022-02-01 17:27:05 +01:00
nds32 perf: Protect perf_guest_cbs with RCU 2022-01-20 09:13:14 +01:00
nios2 nios2: Make NIOS2_DTB_SOURCE_BOOL depend on !COMPILE_TEST 2021-10-27 09:29:07 -05:00
openrisc openrisc: Add clone3 ABI wrapper 2022-01-27 11:04:10 +01:00
parisc parisc: Fix lpa and lpa_user defines 2022-01-27 11:05:12 +01:00
powerpc powerpc/perf: Fix power_pmu_disable to call clear_pmi_irq_pending only if PMI is pending 2022-02-01 17:27:12 +01:00
riscv riscv: dts: microchip: mpfs: Drop empty chosen node 2022-01-27 11:05:28 +01:00
s390 s390/nmi: handle vector validity failures for KVM guests 2022-02-01 17:26:59 +01:00
sh Documentation, arch: Remove leftovers from CIFS_WEAK_PW_HASH 2022-01-27 11:05:21 +01:00
sparc signal: Replace force_fatal_sig with force_exit_sig when in doubt 2021-11-25 09:49:07 +01:00
um um: gitignore: Add kernel/capflags.c 2022-01-27 11:05:34 +01:00
x86 x86/cpu: Add Xeon Icelake-D to list of CPUs that support PPIN 2022-02-01 17:27:06 +01:00
xtensa xtensa: xtfpga: Try software restart before simulating CPU reset 2021-10-05 12:19:05 -07:00
.gitignore
Kconfig arch/cc: Introduce a function to check for confidential computing features 2021-11-18 19:17:21 +01:00