* Oops (NULL pointer) with 'perf record' of selftest 'null_syscall'
@ 2021-06-15 15:05 Christophe Leroy
2021-06-16 3:23 ` Madhavan Srinivasan
0 siblings, 1 reply; 9+ messages in thread
From: Christophe Leroy @ 2021-06-15 15:05 UTC (permalink / raw)
To: linuxppc-dev, linux-kernel
For your information, I'm getting the following Oops. Detected with 5.13-rc6, it also oopses on 5.12
and 5.11.
Runs ok on 5.10. I'm starting bisecting now.
root@vgoippro:/tmp# perf record /root/null_syscall
[ 285.559987] BUG: Kernel NULL pointer dereference on read at 0x00000040
[ 285.566533] Faulting instruction address: 0xc0021f0c
[ 285.571486] Oops: Kernel access of bad area, sig: 11 [#1]
[ 285.576872] BE PAGE_SIZE=4K PREEMPT CMPCPRO
[ 285.581080] SAF3000 DIE NOTIFICATION
[ 285.584661] CPU: 0 PID: 442 Comm: null_syscall Not tainted 5.13.0-rc6-s3k-dev-01645-g7649ee3d2957
#5164
[ 285.594035] NIP: c0021f0c LR: c00e8ad8 CTR: c00d8a5c
[ 285.599074] REGS: e67757d0 TRAP: 0300 Not tainted (5.13.0-rc6-s3k-dev-01645-g7649ee3d2957)
[ 285.607576] MSR: 00001032 <ME,IR,DR,RI> CR: 44775b18 XER: 20000000
[ 285.614063] DAR: 00000040 DSISR: 20000000
[ 285.614063] GPR00: c00e8810 e6775880 c1c52640 e6775b20 7cb36ae0 f0000028 43ebeedc 5ccc47d0
[ 285.614063] GPR08: 00000000 00000900 e6775b20 00000001 00000000 1025b2c0 10013088 10012ee0
[ 285.614063] GPR16: b0000000 00000007 00000001 c00deb64 00000042 00000001 78db7b23 c0b13200
[ 285.614063] GPR24: 00000000 00000000 00000000 e6775b20 c13b8560 00000107 e6775940 e67758e8
[ 285.651693] NIP [c0021f0c] perf_instruction_pointer+0x10/0x60
[ 285.657460] LR [c00e8ad8] perf_prepare_sample+0x344/0x674
[ 285.662859] Call Trace:
[ 285.665301] [e6775880] [c00e8810] perf_prepare_sample+0x7c/0x674 (unreliable)
[ 285.672452] [e67758c0] [c00e8e44] perf_event_output_forward+0x3c/0x94
[ 285.678903] [e6775910] [c00dea8c] __perf_event_overflow+0x74/0x14c
[ 285.685108] [e6775930] [c00dec5c] perf_swevent_hrtimer+0xf8/0x170
[ 285.691217] [e6775a40] [c008c8d0] __hrtimer_run_queues.constprop.0+0x160/0x318
[ 285.698456] [e6775a90] [c008d94c] hrtimer_interrupt+0x148/0x3b0
[ 285.704394] [e6775ae0] [c000c0c0] timer_interrupt+0xc4/0x22c
[ 285.710067] [e6775b10] [c00046f0] Decrementer_virt+0xb8/0xbc
[ 285.715744] --- interrupt: 900 at pagecache_get_page+0x210/0x430
[ 285.721764] NIP: c00f52a8 LR: c00f5408 CTR: c00f59d8
[ 285.726805] REGS: e6775b20 TRAP: 0900 Not tainted (5.13.0-rc6-s3k-dev-01645-g7649ee3d2957)
[ 285.735306] MSR: 00009032 <EE,ME,IR,DR,RI> CR: 28422d68 XER: 00000000
[ 285.742056]
[ 285.742056] GPR00: c00f513c e6775bd0 c1c52640 c1c52640 00000000 00000000 00000000 c1382c38
[ 285.742056] GPR08: 00000000 00000000 00000001 00000000 88482d68 1025b2c0 10013088 10012ee0
[ 285.742056] GPR16: b0000000 00000007 00000001 10012ee0 c18187ac c0b87800 61c88647 c0c18c00
[ 285.742056] GPR24: 00000001 00000003 00000000 00000002 c18187a8 00100cca 00000044 00000000
[ 285.777079] NIP [c00f52a8] pagecache_get_page+0x210/0x430
[ 285.782482] LR [c00f5408] pagecache_get_page+0x370/0x430
[ 285.787796] --- interrupt: 900
[ 285.790843] [e6775bd0] [c00f513c] pagecache_get_page+0xa4/0x430 (unreliable)
[ 285.797910] [e6775c30] [c00f5ca8] filemap_fault+0x2d0/0x8e8
[ 285.803500] [e6775ca0] [c012d244] __do_fault+0x4c/0xd8
[ 285.808666] [e6775cb0] [c0130f64] handle_mm_fault+0x274/0x10b8
[ 285.814517] [e6775d30] [c0014f58] do_page_fault+0x1d4/0x67c
[ 285.820117] [e6775d60] [c000424c] DataAccess_virt+0xd4/0xe4
[ 285.825707] --- interrupt: 300 at __arch_clear_user+0x10/0xcc
[ 285.831458] NIP: c001a3cc LR: c01d5cfc CTR: 00000000
[ 285.836497] REGS: e6775d70 TRAP: 0300 Not tainted (5.13.0-rc6-s3k-dev-01645-g7649ee3d2957)
[ 285.845000] MSR: 00009032 <EE,ME,IR,DR,RI> CR: 48004264 XER: 20000000
[ 285.851751] DAR: 10012ee0 DSISR: 22000000
[ 285.851751] GPR00: c01d53fc e6775e20 c1c52640 00000000 00000120 00000008 c136241c 00000000
[ 285.851751] GPR08: 00000000 9ffed120 10012ee0 00000004 28004868 1025b2c0 10013088 10012ee0
[ 285.851751] GPR16: b0000000 00000007 00000001 10012ee0 10000000 10012d0c 10000000 c1d74240
[ 285.851751] GPR24: 10012ee0 00000000 c1345e80 c1343dc0 10000b38 00000000 c132ec00 c1386a00
[ 285.889384] NIP [c001a3cc] __arch_clear_user+0x10/0xcc
[ 285.894527] LR [c01d5cfc] load_elf_binary+0xec4/0x1340
[ 285.899682] --- interrupt: 300
[ 285.902730] [e6775e20] [c01d53fc] load_elf_binary+0x5c4/0x1340 (unreliable)
[ 285.909713] [e6775ea0] [c0163258] bprm_execve+0x200/0x55c
[ 285.915138] [e6775ef0] [c0163e00] do_execveat_common+0x178/0x1f4
[ 285.921162] [e6775f20] [c0165558] sys_execve+0x40/0x58
[ 285.926321] [e6775f40] [c001404c] ret_from_syscall+0x0/0x28
[ 285.931917] --- interrupt: c00 at 0xfc3ce78
[ 285.936097] NIP: 0fc3ce78 LR: 0fc3d7cc CTR: c01657cc
[ 285.941135] REGS: e6775f50 TRAP: 0c00 Not tainted (5.13.0-rc6-s3k-dev-01645-g7649ee3d2957)
[ 285.949636] MSR: 0000d032 <EE,PR,ME,IR,DR,RI> CR: 22004868 XER: 20000000
[ 285.956655]
[ 285.956655] GPR00: 0000000b afab1bf0 a7d77a50 afab6ee1 afab64c8 104bd9b0 fefefeff 7f7f7f7f
[ 285.956655] GPR08: afab6ee0 00000000 006df8f9 0000011d 24004864 1025b2c0 10231a50 10249108
[ 285.956655] GPR16: 104beeb0 10254830 105dd3f4 10250000 1018a124 10188448 10234e58 00000000
[ 285.956655] GPR24: 10231ae0 00000003 00000001 104bd9b0 afab64c8 afab6ee1 0fd25244 afab1bf0
[ 285.991684] NIP [0fc3ce78] 0xfc3ce78
[ 285.995257] LR [0fc3d7cc] 0xfc3d7cc
[ 285.998742] --- interrupt: c00
[ 286.001789] Instruction dump:
[ 286.004757] 3d20c07d 80a40010 3889847c 486bc444 80630084 546397fe 38630001 4e800020
[ 286.012556] 3d20c0b9 7c6a1b78 810915e4 812300a0 <81080040> 55290036 2c090f00 5508056a
[ 286.020531] ---[ end trace e381e6fcc2db5226 ]---
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: Oops (NULL pointer) with 'perf record' of selftest 'null_syscall'
2021-06-15 15:05 Oops (NULL pointer) with 'perf record' of selftest 'null_syscall' Christophe Leroy
@ 2021-06-16 3:23 ` Madhavan Srinivasan
2021-06-16 3:40 ` Athira Rajeev
0 siblings, 1 reply; 9+ messages in thread
From: Madhavan Srinivasan @ 2021-06-16 3:23 UTC (permalink / raw)
To: linuxppc-dev
On 6/15/21 8:35 PM, Christophe Leroy wrote:
> For your information, I'm getting the following Oops. Detected with
> 5.13-rc6, it also oopses on 5.12 and 5.11.
> Runs ok on 5.10. I'm starting bisecting now.
Thanks for reporting, got the issue. What has happened in this case is
that, pmu device is not registered
and trying to access the instruction point which will land in
perf_instruction_pointer(). And recently I have added
a workaround patch for power10 DD1 which has caused this breakage. My
bad. We are working on a fix patch
for the same and will post it out. Sorry again.
Maddy
>
> root@vgoippro:/tmp# perf record /root/null_syscall
> [ 285.559987] BUG: Kernel NULL pointer dereference on read at 0x00000040
> [ 285.566533] Faulting instruction address: 0xc0021f0c
> [ 285.571486] Oops: Kernel access of bad area, sig: 11 [#1]
> [ 285.576872] BE PAGE_SIZE=4K PREEMPT CMPCPRO
> [ 285.581080] SAF3000 DIE NOTIFICATION
> [ 285.584661] CPU: 0 PID: 442 Comm: null_syscall Not tainted
> 5.13.0-rc6-s3k-dev-01645-g7649ee3d2957 #5164
> [ 285.594035] NIP: c0021f0c LR: c00e8ad8 CTR: c00d8a5c
> [ 285.599074] REGS: e67757d0 TRAP: 0300 Not tainted
> (5.13.0-rc6-s3k-dev-01645-g7649ee3d2957)
> [ 285.607576] MSR: 00001032 <ME,IR,DR,RI> CR: 44775b18 XER: 20000000
> [ 285.614063] DAR: 00000040 DSISR: 20000000
> [ 285.614063] GPR00: c00e8810 e6775880 c1c52640 e6775b20 7cb36ae0
> f0000028 43ebeedc 5ccc47d0
> [ 285.614063] GPR08: 00000000 00000900 e6775b20 00000001 00000000
> 1025b2c0 10013088 10012ee0
> [ 285.614063] GPR16: b0000000 00000007 00000001 c00deb64 00000042
> 00000001 78db7b23 c0b13200
> [ 285.614063] GPR24: 00000000 00000000 00000000 e6775b20 c13b8560
> 00000107 e6775940 e67758e8
> [ 285.651693] NIP [c0021f0c] perf_instruction_pointer+0x10/0x60
> [ 285.657460] LR [c00e8ad8] perf_prepare_sample+0x344/0x674
> [ 285.662859] Call Trace:
> [ 285.665301] [e6775880] [c00e8810] perf_prepare_sample+0x7c/0x674
> (unreliable)
> [ 285.672452] [e67758c0] [c00e8e44] perf_event_output_forward+0x3c/0x94
> [ 285.678903] [e6775910] [c00dea8c] __perf_event_overflow+0x74/0x14c
> [ 285.685108] [e6775930] [c00dec5c] perf_swevent_hrtimer+0xf8/0x170
> [ 285.691217] [e6775a40] [c008c8d0]
> __hrtimer_run_queues.constprop.0+0x160/0x318
> [ 285.698456] [e6775a90] [c008d94c] hrtimer_interrupt+0x148/0x3b0
> [ 285.704394] [e6775ae0] [c000c0c0] timer_interrupt+0xc4/0x22c
> [ 285.710067] [e6775b10] [c00046f0] Decrementer_virt+0xb8/0xbc
> [ 285.715744] --- interrupt: 900 at pagecache_get_page+0x210/0x430
> [ 285.721764] NIP: c00f52a8 LR: c00f5408 CTR: c00f59d8
> [ 285.726805] REGS: e6775b20 TRAP: 0900 Not tainted
> (5.13.0-rc6-s3k-dev-01645-g7649ee3d2957)
> [ 285.735306] MSR: 00009032 <EE,ME,IR,DR,RI> CR: 28422d68 XER:
> 00000000
> [ 285.742056]
> [ 285.742056] GPR00: c00f513c e6775bd0 c1c52640 c1c52640 00000000
> 00000000 00000000 c1382c38
> [ 285.742056] GPR08: 00000000 00000000 00000001 00000000 88482d68
> 1025b2c0 10013088 10012ee0
> [ 285.742056] GPR16: b0000000 00000007 00000001 10012ee0 c18187ac
> c0b87800 61c88647 c0c18c00
> [ 285.742056] GPR24: 00000001 00000003 00000000 00000002 c18187a8
> 00100cca 00000044 00000000
> [ 285.777079] NIP [c00f52a8] pagecache_get_page+0x210/0x430
> [ 285.782482] LR [c00f5408] pagecache_get_page+0x370/0x430
> [ 285.787796] --- interrupt: 900
> [ 285.790843] [e6775bd0] [c00f513c] pagecache_get_page+0xa4/0x430
> (unreliable)
> [ 285.797910] [e6775c30] [c00f5ca8] filemap_fault+0x2d0/0x8e8
> [ 285.803500] [e6775ca0] [c012d244] __do_fault+0x4c/0xd8
> [ 285.808666] [e6775cb0] [c0130f64] handle_mm_fault+0x274/0x10b8
> [ 285.814517] [e6775d30] [c0014f58] do_page_fault+0x1d4/0x67c
> [ 285.820117] [e6775d60] [c000424c] DataAccess_virt+0xd4/0xe4
> [ 285.825707] --- interrupt: 300 at __arch_clear_user+0x10/0xcc
> [ 285.831458] NIP: c001a3cc LR: c01d5cfc CTR: 00000000
> [ 285.836497] REGS: e6775d70 TRAP: 0300 Not tainted
> (5.13.0-rc6-s3k-dev-01645-g7649ee3d2957)
> [ 285.845000] MSR: 00009032 <EE,ME,IR,DR,RI> CR: 48004264 XER:
> 20000000
> [ 285.851751] DAR: 10012ee0 DSISR: 22000000
> [ 285.851751] GPR00: c01d53fc e6775e20 c1c52640 00000000 00000120
> 00000008 c136241c 00000000
> [ 285.851751] GPR08: 00000000 9ffed120 10012ee0 00000004 28004868
> 1025b2c0 10013088 10012ee0
> [ 285.851751] GPR16: b0000000 00000007 00000001 10012ee0 10000000
> 10012d0c 10000000 c1d74240
> [ 285.851751] GPR24: 10012ee0 00000000 c1345e80 c1343dc0 10000b38
> 00000000 c132ec00 c1386a00
> [ 285.889384] NIP [c001a3cc] __arch_clear_user+0x10/0xcc
> [ 285.894527] LR [c01d5cfc] load_elf_binary+0xec4/0x1340
> [ 285.899682] --- interrupt: 300
> [ 285.902730] [e6775e20] [c01d53fc] load_elf_binary+0x5c4/0x1340
> (unreliable)
> [ 285.909713] [e6775ea0] [c0163258] bprm_execve+0x200/0x55c
> [ 285.915138] [e6775ef0] [c0163e00] do_execveat_common+0x178/0x1f4
> [ 285.921162] [e6775f20] [c0165558] sys_execve+0x40/0x58
> [ 285.926321] [e6775f40] [c001404c] ret_from_syscall+0x0/0x28
> [ 285.931917] --- interrupt: c00 at 0xfc3ce78
> [ 285.936097] NIP: 0fc3ce78 LR: 0fc3d7cc CTR: c01657cc
> [ 285.941135] REGS: e6775f50 TRAP: 0c00 Not tainted
> (5.13.0-rc6-s3k-dev-01645-g7649ee3d2957)
> [ 285.949636] MSR: 0000d032 <EE,PR,ME,IR,DR,RI> CR: 22004868 XER:
> 20000000
> [ 285.956655]
> [ 285.956655] GPR00: 0000000b afab1bf0 a7d77a50 afab6ee1 afab64c8
> 104bd9b0 fefefeff 7f7f7f7f
> [ 285.956655] GPR08: afab6ee0 00000000 006df8f9 0000011d 24004864
> 1025b2c0 10231a50 10249108
> [ 285.956655] GPR16: 104beeb0 10254830 105dd3f4 10250000 1018a124
> 10188448 10234e58 00000000
> [ 285.956655] GPR24: 10231ae0 00000003 00000001 104bd9b0 afab64c8
> afab6ee1 0fd25244 afab1bf0
> [ 285.991684] NIP [0fc3ce78] 0xfc3ce78
> [ 285.995257] LR [0fc3d7cc] 0xfc3d7cc
> [ 285.998742] --- interrupt: c00
> [ 286.001789] Instruction dump:
> [ 286.004757] 3d20c07d 80a40010 3889847c 486bc444 80630084 546397fe
> 38630001 4e800020
> [ 286.012556] 3d20c0b9 7c6a1b78 810915e4 812300a0 <81080040> 55290036
> 2c090f00 5508056a
> [ 286.020531] ---[ end trace e381e6fcc2db5226 ]---
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: Oops (NULL pointer) with 'perf record' of selftest 'null_syscall'
2021-06-16 3:23 ` Madhavan Srinivasan
@ 2021-06-16 3:40 ` Athira Rajeev
2021-06-16 6:26 ` Christophe Leroy
0 siblings, 1 reply; 9+ messages in thread
From: Athira Rajeev @ 2021-06-16 3:40 UTC (permalink / raw)
To: Madhavan Srinivasan, Christophe Leroy; +Cc: linuxppc-dev
> On 16-Jun-2021, at 8:53 AM, Madhavan Srinivasan <maddy@linux.ibm.com> wrote:
>
>
> On 6/15/21 8:35 PM, Christophe Leroy wrote:
>> For your information, I'm getting the following Oops. Detected with 5.13-rc6, it also oopses on 5.12 and 5.11.
>> Runs ok on 5.10. I'm starting bisecting now.
>
>
> Thanks for reporting, got the issue. What has happened in this case is that, pmu device is not registered
> and trying to access the instruction point which will land in perf_instruction_pointer(). And recently I have added
> a workaround patch for power10 DD1 which has caused this breakage. My bad. We are working on a fix patch
> for the same and will post it out. Sorry again.
>
Hi Christophe,
Can you please try with below patch in your environment and test if it works for you.
From 55d3afc9369dfbe28a7152c8e9f856c11c7fe43d Mon Sep 17 00:00:00 2001
From: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Date: Tue, 15 Jun 2021 22:28:11 -0400
Subject: [PATCH] powerpc/perf: Fix crash with 'perf_instruction_pointer' when
pmu is not set
On systems without any specific PMU driver support registered, running
perf record causes oops:
[ 38.841073] NIP [c00000000013af54] perf_instruction_pointer+0x24/0x100
[ 38.841079] LR [c0000000003c7358] perf_prepare_sample+0x4e8/0x820
[ 38.841085] --- interrupt: 300
[ 38.841088] [c00000001cf03440] [c0000000003c6ef8] perf_prepare_sample+0x88/0x820 (unreliable)
[ 38.841096] [c00000001cf034a0] [c0000000003c76d0] perf_event_output_forward+0x40/0xc0
[ 38.841104] [c00000001cf03520] [c0000000003b45e8] __perf_event_overflow+0x88/0x1b0
[ 38.841112] [c00000001cf03570] [c0000000003b480c] perf_swevent_hrtimer+0xfc/0x1a0
[ 38.841119] [c00000001cf03740] [c0000000002399cc] __hrtimer_run_queues+0x17c/0x380
[ 38.841127] [c00000001cf037c0] [c00000000023a5f8] hrtimer_interrupt+0x128/0x2f0
[ 38.841135] [c00000001cf03870] [c00000000002962c] timer_interrupt+0x13c/0x370
[ 38.841143i] [c00000001cf038d0] [c000000000009ba4] decrementer_common_virt+0x1a4/0x1b0
[ 38.841151] --- interrupt: 900 at copypage_power7+0xd4/0x1c0
During perf record session, perf_instruction_pointer() is called to
capture the sample ip. This function in core-book3s accesses ppmu->flags.
If a platform specific PMU driver is not registered, ppmu is set to NULL
and accessing its members results in a crash. Fix this crash by checking
if ppmu is set.
Signed-off-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Reported-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
arch/powerpc/perf/core-book3s.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/powerpc/perf/core-book3s.c b/arch/powerpc/perf/core-book3s.c
index 16d4d1b6a1ff..816756588cb7 100644
--- a/arch/powerpc/perf/core-book3s.c
+++ b/arch/powerpc/perf/core-book3s.c
@@ -2254,7 +2254,7 @@ unsigned long perf_instruction_pointer(struct pt_regs *regs)
bool use_siar = regs_use_siar(regs);
unsigned long siar = mfspr(SPRN_SIAR);
- if (ppmu->flags & PPMU_P10_DD1) {
+ if (ppmu && ppmu->flags & PPMU_P10_DD1) {
if (siar)
return siar;
else
--
2.27.0
Thanks
Athira
> Maddy
>
>
>>
>> root@vgoippro:/tmp# perf record /root/null_syscall
>> [ 285.559987] BUG: Kernel NULL pointer dereference on read at 0x00000040
>> [ 285.566533] Faulting instruction address: 0xc0021f0c
>> [ 285.571486] Oops: Kernel access of bad area, sig: 11 [#1]
>> [ 285.576872] BE PAGE_SIZE=4K PREEMPT CMPCPRO
>> [ 285.581080] SAF3000 DIE NOTIFICATION
>> [ 285.584661] CPU: 0 PID: 442 Comm: null_syscall Not tainted 5.13.0-rc6-s3k-dev-01645-g7649ee3d2957 #5164
>> [ 285.594035] NIP: c0021f0c LR: c00e8ad8 CTR: c00d8a5c
>> [ 285.599074] REGS: e67757d0 TRAP: 0300 Not tainted (5.13.0-rc6-s3k-dev-01645-g7649ee3d2957)
>> [ 285.607576] MSR: 00001032 <ME,IR,DR,RI> CR: 44775b18 XER: 20000000
>> [ 285.614063] DAR: 00000040 DSISR: 20000000
>> [ 285.614063] GPR00: c00e8810 e6775880 c1c52640 e6775b20 7cb36ae0 f0000028 43ebeedc 5ccc47d0
>> [ 285.614063] GPR08: 00000000 00000900 e6775b20 00000001 00000000 1025b2c0 10013088 10012ee0
>> [ 285.614063] GPR16: b0000000 00000007 00000001 c00deb64 00000042 00000001 78db7b23 c0b13200
>> [ 285.614063] GPR24: 00000000 00000000 00000000 e6775b20 c13b8560 00000107 e6775940 e67758e8
>> [ 285.651693] NIP [c0021f0c] perf_instruction_pointer+0x10/0x60
>> [ 285.657460] LR [c00e8ad8] perf_prepare_sample+0x344/0x674
>> [ 285.662859] Call Trace:
>> [ 285.665301] [e6775880] [c00e8810] perf_prepare_sample+0x7c/0x674 (unreliable)
>> [ 285.672452] [e67758c0] [c00e8e44] perf_event_output_forward+0x3c/0x94
>> [ 285.678903] [e6775910] [c00dea8c] __perf_event_overflow+0x74/0x14c
>> [ 285.685108] [e6775930] [c00dec5c] perf_swevent_hrtimer+0xf8/0x170
>> [ 285.691217] [e6775a40] [c008c8d0] __hrtimer_run_queues.constprop.0+0x160/0x318
>> [ 285.698456] [e6775a90] [c008d94c] hrtimer_interrupt+0x148/0x3b0
>> [ 285.704394] [e6775ae0] [c000c0c0] timer_interrupt+0xc4/0x22c
>> [ 285.710067] [e6775b10] [c00046f0] Decrementer_virt+0xb8/0xbc
>> [ 285.715744] --- interrupt: 900 at pagecache_get_page+0x210/0x430
>> [ 285.721764] NIP: c00f52a8 LR: c00f5408 CTR: c00f59d8
>> [ 285.726805] REGS: e6775b20 TRAP: 0900 Not tainted (5.13.0-rc6-s3k-dev-01645-g7649ee3d2957)
>> [ 285.735306] MSR: 00009032 <EE,ME,IR,DR,RI> CR: 28422d68 XER: 00000000
>> [ 285.742056]
>> [ 285.742056] GPR00: c00f513c e6775bd0 c1c52640 c1c52640 00000000 00000000 00000000 c1382c38
>> [ 285.742056] GPR08: 00000000 00000000 00000001 00000000 88482d68 1025b2c0 10013088 10012ee0
>> [ 285.742056] GPR16: b0000000 00000007 00000001 10012ee0 c18187ac c0b87800 61c88647 c0c18c00
>> [ 285.742056] GPR24: 00000001 00000003 00000000 00000002 c18187a8 00100cca 00000044 00000000
>> [ 285.777079] NIP [c00f52a8] pagecache_get_page+0x210/0x430
>> [ 285.782482] LR [c00f5408] pagecache_get_page+0x370/0x430
>> [ 285.787796] --- interrupt: 900
>> [ 285.790843] [e6775bd0] [c00f513c] pagecache_get_page+0xa4/0x430 (unreliable)
>> [ 285.797910] [e6775c30] [c00f5ca8] filemap_fault+0x2d0/0x8e8
>> [ 285.803500] [e6775ca0] [c012d244] __do_fault+0x4c/0xd8
>> [ 285.808666] [e6775cb0] [c0130f64] handle_mm_fault+0x274/0x10b8
>> [ 285.814517] [e6775d30] [c0014f58] do_page_fault+0x1d4/0x67c
>> [ 285.820117] [e6775d60] [c000424c] DataAccess_virt+0xd4/0xe4
>> [ 285.825707] --- interrupt: 300 at __arch_clear_user+0x10/0xcc
>> [ 285.831458] NIP: c001a3cc LR: c01d5cfc CTR: 00000000
>> [ 285.836497] REGS: e6775d70 TRAP: 0300 Not tainted (5.13.0-rc6-s3k-dev-01645-g7649ee3d2957)
>> [ 285.845000] MSR: 00009032 <EE,ME,IR,DR,RI> CR: 48004264 XER: 20000000
>> [ 285.851751] DAR: 10012ee0 DSISR: 22000000
>> [ 285.851751] GPR00: c01d53fc e6775e20 c1c52640 00000000 00000120 00000008 c136241c 00000000
>> [ 285.851751] GPR08: 00000000 9ffed120 10012ee0 00000004 28004868 1025b2c0 10013088 10012ee0
>> [ 285.851751] GPR16: b0000000 00000007 00000001 10012ee0 10000000 10012d0c 10000000 c1d74240
>> [ 285.851751] GPR24: 10012ee0 00000000 c1345e80 c1343dc0 10000b38 00000000 c132ec00 c1386a00
>> [ 285.889384] NIP [c001a3cc] __arch_clear_user+0x10/0xcc
>> [ 285.894527] LR [c01d5cfc] load_elf_binary+0xec4/0x1340
>> [ 285.899682] --- interrupt: 300
>> [ 285.902730] [e6775e20] [c01d53fc] load_elf_binary+0x5c4/0x1340 (unreliable)
>> [ 285.909713] [e6775ea0] [c0163258] bprm_execve+0x200/0x55c
>> [ 285.915138] [e6775ef0] [c0163e00] do_execveat_common+0x178/0x1f4
>> [ 285.921162] [e6775f20] [c0165558] sys_execve+0x40/0x58
>> [ 285.926321] [e6775f40] [c001404c] ret_from_syscall+0x0/0x28
>> [ 285.931917] --- interrupt: c00 at 0xfc3ce78
>> [ 285.936097] NIP: 0fc3ce78 LR: 0fc3d7cc CTR: c01657cc
>> [ 285.941135] REGS: e6775f50 TRAP: 0c00 Not tainted (5.13.0-rc6-s3k-dev-01645-g7649ee3d2957)
>> [ 285.949636] MSR: 0000d032 <EE,PR,ME,IR,DR,RI> CR: 22004868 XER: 20000000
>> [ 285.956655]
>> [ 285.956655] GPR00: 0000000b afab1bf0 a7d77a50 afab6ee1 afab64c8 104bd9b0 fefefeff 7f7f7f7f
>> [ 285.956655] GPR08: afab6ee0 00000000 006df8f9 0000011d 24004864 1025b2c0 10231a50 10249108
>> [ 285.956655] GPR16: 104beeb0 10254830 105dd3f4 10250000 1018a124 10188448 10234e58 00000000
>> [ 285.956655] GPR24: 10231ae0 00000003 00000001 104bd9b0 afab64c8 afab6ee1 0fd25244 afab1bf0
>> [ 285.991684] NIP [0fc3ce78] 0xfc3ce78
>> [ 285.995257] LR [0fc3d7cc] 0xfc3d7cc
>> [ 285.998742] --- interrupt: c00
>> [ 286.001789] Instruction dump:
>> [ 286.004757] 3d20c07d 80a40010 3889847c 486bc444 80630084 546397fe 38630001 4e800020
>> [ 286.012556] 3d20c0b9 7c6a1b78 810915e4 812300a0 <81080040> 55290036 2c090f00 5508056a
>> [ 286.020531] ---[ end trace e381e6fcc2db5226 ]---
^ permalink raw reply related [flat|nested] 9+ messages in thread
* Re: Oops (NULL pointer) with 'perf record' of selftest 'null_syscall'
2021-06-16 3:40 ` Athira Rajeev
@ 2021-06-16 6:26 ` Christophe Leroy
2021-06-16 6:33 ` Madhavan Srinivasan
2021-06-17 6:36 ` Athira Rajeev
0 siblings, 2 replies; 9+ messages in thread
From: Christophe Leroy @ 2021-06-16 6:26 UTC (permalink / raw)
To: Athira Rajeev, Madhavan Srinivasan; +Cc: linuxppc-dev
Le 16/06/2021 à 05:40, Athira Rajeev a écrit :
>
>
>> On 16-Jun-2021, at 8:53 AM, Madhavan Srinivasan <maddy@linux.ibm.com> wrote:
>>
>>
>> On 6/15/21 8:35 PM, Christophe Leroy wrote:
>>> For your information, I'm getting the following Oops. Detected with 5.13-rc6, it also oopses on 5.12 and 5.11.
>>> Runs ok on 5.10. I'm starting bisecting now.
>>
>>
>> Thanks for reporting, got the issue. What has happened in this case is that, pmu device is not registered
>> and trying to access the instruction point which will land in perf_instruction_pointer(). And recently I have added
>> a workaround patch for power10 DD1 which has caused this breakage. My bad. We are working on a fix patch
>> for the same and will post it out. Sorry again.
>>
>
> Hi Christophe,
>
> Can you please try with below patch in your environment and test if it works for you.
>
> From 55d3afc9369dfbe28a7152c8e9f856c11c7fe43d Mon Sep 17 00:00:00 2001
> From: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
> Date: Tue, 15 Jun 2021 22:28:11 -0400
> Subject: [PATCH] powerpc/perf: Fix crash with 'perf_instruction_pointer' when
> pmu is not set
>
> On systems without any specific PMU driver support registered, running
> perf record causes oops:
>
> [ 38.841073] NIP [c00000000013af54] perf_instruction_pointer+0x24/0x100
> [ 38.841079] LR [c0000000003c7358] perf_prepare_sample+0x4e8/0x820
> [ 38.841085] --- interrupt: 300
> [ 38.841088] [c00000001cf03440] [c0000000003c6ef8] perf_prepare_sample+0x88/0x820 (unreliable)
> [ 38.841096] [c00000001cf034a0] [c0000000003c76d0] perf_event_output_forward+0x40/0xc0
> [ 38.841104] [c00000001cf03520] [c0000000003b45e8] __perf_event_overflow+0x88/0x1b0
> [ 38.841112] [c00000001cf03570] [c0000000003b480c] perf_swevent_hrtimer+0xfc/0x1a0
> [ 38.841119] [c00000001cf03740] [c0000000002399cc] __hrtimer_run_queues+0x17c/0x380
> [ 38.841127] [c00000001cf037c0] [c00000000023a5f8] hrtimer_interrupt+0x128/0x2f0
> [ 38.841135] [c00000001cf03870] [c00000000002962c] timer_interrupt+0x13c/0x370
> [ 38.841143i] [c00000001cf038d0] [c000000000009ba4] decrementer_common_virt+0x1a4/0x1b0
> [ 38.841151] --- interrupt: 900 at copypage_power7+0xd4/0x1c0
>
> During perf record session, perf_instruction_pointer() is called to
> capture the sample ip. This function in core-book3s accesses ppmu->flags.
> If a platform specific PMU driver is not registered, ppmu is set to NULL
> and accessing its members results in a crash. Fix this crash by checking
> if ppmu is set.
>
> Signed-off-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
> Reported-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Fixes: 2ca13a4cc56c ("powerpc/perf: Use regs->nip when SIAR is zero")
Cc: stable@vger.kernel.org
Tested-by: Christophe Leroy <christophe.leroy@csgroup.eu>
> ---
> arch/powerpc/perf/core-book3s.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/arch/powerpc/perf/core-book3s.c b/arch/powerpc/perf/core-book3s.c
> index 16d4d1b6a1ff..816756588cb7 100644
> --- a/arch/powerpc/perf/core-book3s.c
> +++ b/arch/powerpc/perf/core-book3s.c
> @@ -2254,7 +2254,7 @@ unsigned long perf_instruction_pointer(struct pt_regs *regs)
> bool use_siar = regs_use_siar(regs);
> unsigned long siar = mfspr(SPRN_SIAR);
>
> - if (ppmu->flags & PPMU_P10_DD1) {
> + if (ppmu && ppmu->flags & PPMU_P10_DD1) {
> if (siar)
> return siar;
> else
>
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: Oops (NULL pointer) with 'perf record' of selftest 'null_syscall'
2021-06-16 6:26 ` Christophe Leroy
@ 2021-06-16 6:33 ` Madhavan Srinivasan
2021-06-16 6:48 ` Christophe Leroy
2021-06-17 6:36 ` Athira Rajeev
1 sibling, 1 reply; 9+ messages in thread
From: Madhavan Srinivasan @ 2021-06-16 6:33 UTC (permalink / raw)
To: Christophe Leroy, Athira Rajeev; +Cc: linuxppc-dev
On 6/16/21 11:56 AM, Christophe Leroy wrote:
>
>
> Le 16/06/2021 à 05:40, Athira Rajeev a écrit :
>>
>>
>>> On 16-Jun-2021, at 8:53 AM, Madhavan Srinivasan
>>> <maddy@linux.ibm.com> wrote:
>>>
>>>
>>> On 6/15/21 8:35 PM, Christophe Leroy wrote:
>>>> For your information, I'm getting the following Oops. Detected with
>>>> 5.13-rc6, it also oopses on 5.12 and 5.11.
>>>> Runs ok on 5.10. I'm starting bisecting now.
>>>
>>>
>>> Thanks for reporting, got the issue. What has happened in this case
>>> is that, pmu device is not registered
>>> and trying to access the instruction point which will land in
>>> perf_instruction_pointer(). And recently I have added
>>> a workaround patch for power10 DD1 which has caused this breakage.
>>> My bad. We are working on a fix patch
>>> for the same and will post it out. Sorry again.
>>>
>>
>> Hi Christophe,
>>
>> Can you please try with below patch in your environment and test if
>> it works for you.
>>
>> From 55d3afc9369dfbe28a7152c8e9f856c11c7fe43d Mon Sep 17 00:00:00 2001
>> From: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
>> Date: Tue, 15 Jun 2021 22:28:11 -0400
>> Subject: [PATCH] powerpc/perf: Fix crash with
>> 'perf_instruction_pointer' when
>> pmu is not set
>>
>> On systems without any specific PMU driver support registered, running
>> perf record causes oops:
>>
>> [ 38.841073] NIP [c00000000013af54]
>> perf_instruction_pointer+0x24/0x100
>> [ 38.841079] LR [c0000000003c7358] perf_prepare_sample+0x4e8/0x820
>> [ 38.841085] --- interrupt: 300
>> [ 38.841088] [c00000001cf03440] [c0000000003c6ef8]
>> perf_prepare_sample+0x88/0x820 (unreliable)
>> [ 38.841096] [c00000001cf034a0] [c0000000003c76d0]
>> perf_event_output_forward+0x40/0xc0
>> [ 38.841104] [c00000001cf03520] [c0000000003b45e8]
>> __perf_event_overflow+0x88/0x1b0
>> [ 38.841112] [c00000001cf03570] [c0000000003b480c]
>> perf_swevent_hrtimer+0xfc/0x1a0
>> [ 38.841119] [c00000001cf03740] [c0000000002399cc]
>> __hrtimer_run_queues+0x17c/0x380
>> [ 38.841127] [c00000001cf037c0] [c00000000023a5f8]
>> hrtimer_interrupt+0x128/0x2f0
>> [ 38.841135] [c00000001cf03870] [c00000000002962c]
>> timer_interrupt+0x13c/0x370
>> [ 38.841143i] [c00000001cf038d0] [c000000000009ba4]
>> decrementer_common_virt+0x1a4/0x1b0
>> [ 38.841151] --- interrupt: 900 at copypage_power7+0xd4/0x1c0
>>
>> During perf record session, perf_instruction_pointer() is called to
>> capture the sample ip. This function in core-book3s accesses
>> ppmu->flags.
>> If a platform specific PMU driver is not registered, ppmu is set to NULL
>> and accessing its members results in a crash. Fix this crash by checking
>> if ppmu is set.
>>
>> Signed-off-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
>> Reported-by: Christophe Leroy <christophe.leroy@csgroup.eu>
>
> Fixes: 2ca13a4cc56c ("powerpc/perf: Use regs->nip when SIAR is zero")
> Cc: stable@vger.kernel.org
> Tested-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Thanks, but just wonder what is the system config and processor version
in which you got this fail.
Reason, we do have generic-pmu which should kick-in in absence of a
platform specific driver.
Maddy
>
>> ---
>> arch/powerpc/perf/core-book3s.c | 2 +-
>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/arch/powerpc/perf/core-book3s.c
>> b/arch/powerpc/perf/core-book3s.c
>> index 16d4d1b6a1ff..816756588cb7 100644
>> --- a/arch/powerpc/perf/core-book3s.c
>> +++ b/arch/powerpc/perf/core-book3s.c
>> @@ -2254,7 +2254,7 @@ unsigned long perf_instruction_pointer(struct
>> pt_regs *regs)
>> bool use_siar = regs_use_siar(regs);
>> unsigned long siar = mfspr(SPRN_SIAR);
>> - if (ppmu->flags & PPMU_P10_DD1) {
>> + if (ppmu && ppmu->flags & PPMU_P10_DD1) {
>> if (siar)
>> return siar;
>> else
>>
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: Oops (NULL pointer) with 'perf record' of selftest 'null_syscall'
2021-06-16 6:33 ` Madhavan Srinivasan
@ 2021-06-16 6:48 ` Christophe Leroy
0 siblings, 0 replies; 9+ messages in thread
From: Christophe Leroy @ 2021-06-16 6:48 UTC (permalink / raw)
To: Madhavan Srinivasan, Athira Rajeev; +Cc: linuxppc-dev
Le 16/06/2021 à 08:33, Madhavan Srinivasan a écrit :
>
> On 6/16/21 11:56 AM, Christophe Leroy wrote:
>>
>>
>> Le 16/06/2021 à 05:40, Athira Rajeev a écrit :
>>>
>>>
>>>> On 16-Jun-2021, at 8:53 AM, Madhavan Srinivasan <maddy@linux.ibm.com> wrote:
>>>>
>>>>
>>>> On 6/15/21 8:35 PM, Christophe Leroy wrote:
>>>>> For your information, I'm getting the following Oops. Detected with 5.13-rc6, it also oopses on
>>>>> 5.12 and 5.11.
>>>>> Runs ok on 5.10. I'm starting bisecting now.
>>>>
>>>>
>>>> Thanks for reporting, got the issue. What has happened in this case is that, pmu device is not
>>>> registered
>>>> and trying to access the instruction point which will land in perf_instruction_pointer(). And
>>>> recently I have added
>>>> a workaround patch for power10 DD1 which has caused this breakage. My bad. We are working on a
>>>> fix patch
>>>> for the same and will post it out. Sorry again.
>>>>
>>>
>>> Hi Christophe,
>>>
>>> Can you please try with below patch in your environment and test if it works for you.
>>>
>>> From 55d3afc9369dfbe28a7152c8e9f856c11c7fe43d Mon Sep 17 00:00:00 2001
>>> From: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
>>> Date: Tue, 15 Jun 2021 22:28:11 -0400
>>> Subject: [PATCH] powerpc/perf: Fix crash with 'perf_instruction_pointer' when
>>> pmu is not set
>>>
>>> On systems without any specific PMU driver support registered, running
>>> perf record causes oops:
>>>
>>> [ 38.841073] NIP [c00000000013af54] perf_instruction_pointer+0x24/0x100
>>> [ 38.841079] LR [c0000000003c7358] perf_prepare_sample+0x4e8/0x820
>>> [ 38.841085] --- interrupt: 300
>>> [ 38.841088] [c00000001cf03440] [c0000000003c6ef8] perf_prepare_sample+0x88/0x820 (unreliable)
>>> [ 38.841096] [c00000001cf034a0] [c0000000003c76d0] perf_event_output_forward+0x40/0xc0
>>> [ 38.841104] [c00000001cf03520] [c0000000003b45e8] __perf_event_overflow+0x88/0x1b0
>>> [ 38.841112] [c00000001cf03570] [c0000000003b480c] perf_swevent_hrtimer+0xfc/0x1a0
>>> [ 38.841119] [c00000001cf03740] [c0000000002399cc] __hrtimer_run_queues+0x17c/0x380
>>> [ 38.841127] [c00000001cf037c0] [c00000000023a5f8] hrtimer_interrupt+0x128/0x2f0
>>> [ 38.841135] [c00000001cf03870] [c00000000002962c] timer_interrupt+0x13c/0x370
>>> [ 38.841143i] [c00000001cf038d0] [c000000000009ba4] decrementer_common_virt+0x1a4/0x1b0
>>> [ 38.841151] --- interrupt: 900 at copypage_power7+0xd4/0x1c0
>>>
>>> During perf record session, perf_instruction_pointer() is called to
>>> capture the sample ip. This function in core-book3s accesses ppmu->flags.
>>> If a platform specific PMU driver is not registered, ppmu is set to NULL
>>> and accessing its members results in a crash. Fix this crash by checking
>>> if ppmu is set.
>>>
>>> Signed-off-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
>>> Reported-by: Christophe Leroy <christophe.leroy@csgroup.eu>
>>
>> Fixes: 2ca13a4cc56c ("powerpc/perf: Use regs->nip when SIAR is zero")
>> Cc: stable@vger.kernel.org
>> Tested-by: Christophe Leroy <christophe.leroy@csgroup.eu>
> Thanks, but just wonder what is the system config and processor version in which you got this fail.
> Reason, we do have generic-pmu which should kick-in in absence of a platform specific driver.
>
It's an mpc8321 (book3s/32)
Christophe
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: Oops (NULL pointer) with 'perf record' of selftest 'null_syscall'
2021-06-16 6:26 ` Christophe Leroy
2021-06-16 6:33 ` Madhavan Srinivasan
@ 2021-06-17 6:36 ` Athira Rajeev
2021-06-17 16:35 ` Christophe Leroy
1 sibling, 1 reply; 9+ messages in thread
From: Athira Rajeev @ 2021-06-17 6:36 UTC (permalink / raw)
To: Christophe Leroy; +Cc: Madhavan Srinivasan, linuxppc-dev
[-- Attachment #1: Type: text/html, Size: 8288 bytes --]
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: Oops (NULL pointer) with 'perf record' of selftest 'null_syscall'
2021-06-17 6:36 ` Athira Rajeev
@ 2021-06-17 16:35 ` Christophe Leroy
2021-06-17 17:51 ` Athira Rajeev
0 siblings, 1 reply; 9+ messages in thread
From: Christophe Leroy @ 2021-06-17 16:35 UTC (permalink / raw)
To: Athira Rajeev; +Cc: Madhavan Srinivasan, linuxppc-dev
Le 17/06/2021 à 08:36, Athira Rajeev a écrit :
>
>
>> On 16-Jun-2021, at 11:56 AM, Christophe Leroy <christophe.leroy@csgroup.eu> wrote:
>>
>>
>>
>> Le 16/06/2021 à 05:40, Athira Rajeev a écrit :
>>>> On 16-Jun-2021, at 8:53 AM, Madhavan Srinivasan <maddy@linux.ibm.com> wrote:
>>>>
>>>>
>>>> On 6/15/21 8:35 PM, Christophe Leroy wrote:
>>>>> For your information, I'm getting the following Oops. Detected with 5.13-rc6, it also oopses on
>>>>> 5.12 and 5.11.
>>>>> Runs ok on 5.10. I'm starting bisecting now.
>>>>
>>>>
>>>> Thanks for reporting, got the issue. What has happened in this case is that, pmu device is not
>>>> registered
>>>> and trying to access the instruction point which will land in perf_instruction_pointer(). And
>>>> recently I have added
>>>> a workaround patch for power10 DD1 which has caused this breakage. My bad. We are working on a
>>>> fix patch
>>>> for the same and will post it out. Sorry again.
>>>>
>>> Hi Christophe,
>>> Can you please try with below patch in your environment and test if it works for you.
>>> From 55d3afc9369dfbe28a7152c8e9f856c11c7fe43d Mon Sep 17 00:00:00 2001
>>> From: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
>>> Date: Tue, 15 Jun 2021 22:28:11 -0400
>>> Subject: [PATCH] powerpc/perf: Fix crash with 'perf_instruction_pointer' when
>>> pmu is not set
>>> On systems without any specific PMU driver support registered, running
>>> perf record causes oops:
>>> [ 38.841073] NIP [c00000000013af54] perf_instruction_pointer+0x24/0x100
>>> [ 38.841079] LR [c0000000003c7358] perf_prepare_sample+0x4e8/0x820
>>> [ 38.841085] --- interrupt: 300
>>> [ 38.841088] [c00000001cf03440] [c0000000003c6ef8] perf_prepare_sample+0x88/0x820 (unreliable)
>>> [ 38.841096] [c00000001cf034a0] [c0000000003c76d0] perf_event_output_forward+0x40/0xc0
>>> [ 38.841104] [c00000001cf03520] [c0000000003b45e8] __perf_event_overflow+0x88/0x1b0
>>> [ 38.841112] [c00000001cf03570] [c0000000003b480c] perf_swevent_hrtimer+0xfc/0x1a0
>>> [ 38.841119] [c00000001cf03740] [c0000000002399cc] __hrtimer_run_queues+0x17c/0x380
>>> [ 38.841127] [c00000001cf037c0] [c00000000023a5f8] hrtimer_interrupt+0x128/0x2f0
>>> [ 38.841135] [c00000001cf03870] [c00000000002962c] timer_interrupt+0x13c/0x370
>>> [ 38.841143i] [c00000001cf038d0] [c000000000009ba4] decrementer_common_virt+0x1a4/0x1b0
>>> [ 38.841151] --- interrupt: 900 at copypage_power7+0xd4/0x1c0
>>> During perf record session, perf_instruction_pointer() is called to
>>> capture the sample ip. This function in core-book3s accesses ppmu->flags.
>>> If a platform specific PMU driver is not registered, ppmu is set to NULL
>>> and accessing its members results in a crash. Fix this crash by checking
>>> if ppmu is set.
>>> Signed-off-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
>>> Reported-by: Christophe Leroy <christophe.leroy@csgroup.eu>
>>
>> Fixes: 2ca13a4cc56c ("powerpc/perf: Use regs->nip when SIAR is zero")
>> Cc: stable@vger.kernel.org
>> Tested-by: Christophe Leroy <christophe.leroy@csgroup.eu>
>
> Hi Christophe,
>
> Thanks for testing with the change. I have a newer version where I have added braces around the check.
> Can you please check once and can I add your tested-by for the below patch.
Yes it works, you can add my Tested-by:
Please also add Cc: stable@vger.kernel.org, this needs to be backported as soon as possible.
Thanks
Christophe
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: Oops (NULL pointer) with 'perf record' of selftest 'null_syscall'
2021-06-17 16:35 ` Christophe Leroy
@ 2021-06-17 17:51 ` Athira Rajeev
0 siblings, 0 replies; 9+ messages in thread
From: Athira Rajeev @ 2021-06-17 17:51 UTC (permalink / raw)
To: Christophe Leroy; +Cc: Madhavan Srinivasan, linuxppc-dev
> On 17-Jun-2021, at 10:05 PM, Christophe Leroy <christophe.leroy@csgroup.eu> wrote:
>
>
>
> Le 17/06/2021 à 08:36, Athira Rajeev a écrit :
>>> On 16-Jun-2021, at 11:56 AM, Christophe Leroy <christophe.leroy@csgroup.eu> wrote:
>>>
>>>
>>>
>>> Le 16/06/2021 à 05:40, Athira Rajeev a écrit :
>>>>> On 16-Jun-2021, at 8:53 AM, Madhavan Srinivasan <maddy@linux.ibm.com> wrote:
>>>>>
>>>>>
>>>>> On 6/15/21 8:35 PM, Christophe Leroy wrote:
>>>>>> For your information, I'm getting the following Oops. Detected with 5.13-rc6, it also oopses on 5.12 and 5.11.
>>>>>> Runs ok on 5.10. I'm starting bisecting now.
>>>>>
>>>>>
>>>>> Thanks for reporting, got the issue. What has happened in this case is that, pmu device is not registered
>>>>> and trying to access the instruction point which will land in perf_instruction_pointer(). And recently I have added
>>>>> a workaround patch for power10 DD1 which has caused this breakage. My bad. We are working on a fix patch
>>>>> for the same and will post it out. Sorry again.
>>>>>
>>>> Hi Christophe,
>>>> Can you please try with below patch in your environment and test if it works for you.
>>>> From 55d3afc9369dfbe28a7152c8e9f856c11c7fe43d Mon Sep 17 00:00:00 2001
>>>> From: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
>>>> Date: Tue, 15 Jun 2021 22:28:11 -0400
>>>> Subject: [PATCH] powerpc/perf: Fix crash with 'perf_instruction_pointer' when
>>>> pmu is not set
>>>> On systems without any specific PMU driver support registered, running
>>>> perf record causes oops:
>>>> [ 38.841073] NIP [c00000000013af54] perf_instruction_pointer+0x24/0x100
>>>> [ 38.841079] LR [c0000000003c7358] perf_prepare_sample+0x4e8/0x820
>>>> [ 38.841085] --- interrupt: 300
>>>> [ 38.841088] [c00000001cf03440] [c0000000003c6ef8] perf_prepare_sample+0x88/0x820 (unreliable)
>>>> [ 38.841096] [c00000001cf034a0] [c0000000003c76d0] perf_event_output_forward+0x40/0xc0
>>>> [ 38.841104] [c00000001cf03520] [c0000000003b45e8] __perf_event_overflow+0x88/0x1b0
>>>> [ 38.841112] [c00000001cf03570] [c0000000003b480c] perf_swevent_hrtimer+0xfc/0x1a0
>>>> [ 38.841119] [c00000001cf03740] [c0000000002399cc] __hrtimer_run_queues+0x17c/0x380
>>>> [ 38.841127] [c00000001cf037c0] [c00000000023a5f8] hrtimer_interrupt+0x128/0x2f0
>>>> [ 38.841135] [c00000001cf03870] [c00000000002962c] timer_interrupt+0x13c/0x370
>>>> [ 38.841143i] [c00000001cf038d0] [c000000000009ba4] decrementer_common_virt+0x1a4/0x1b0
>>>> [ 38.841151] --- interrupt: 900 at copypage_power7+0xd4/0x1c0
>>>> During perf record session, perf_instruction_pointer() is called to
>>>> capture the sample ip. This function in core-book3s accesses ppmu->flags.
>>>> If a platform specific PMU driver is not registered, ppmu is set to NULL
>>>> and accessing its members results in a crash. Fix this crash by checking
>>>> if ppmu is set.
>>>> Signed-off-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
>>>> Reported-by: Christophe Leroy <christophe.leroy@csgroup.eu>
>>>
>>> Fixes: 2ca13a4cc56c ("powerpc/perf: Use regs->nip when SIAR is zero")
>>> Cc: stable@vger.kernel.org
>>> Tested-by: Christophe Leroy <christophe.leroy@csgroup.eu>
>> Hi Christophe,
>> Thanks for testing with the change. I have a newer version where I have added braces around the check.
>> Can you please check once and can I add your tested-by for the below patch.
>
> Yes it works, you can add my Tested-by:
> Please also add Cc: stable@vger.kernel.org, this needs to be backported as soon as possible.
Sure Christophe, will add Cc also. Thanks for testing.
Athira
>
> Thanks
> Christophe
^ permalink raw reply [flat|nested] 9+ messages in thread
end of thread, other threads:[~2021-06-17 17:54 UTC | newest]
Thread overview: 9+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-06-15 15:05 Oops (NULL pointer) with 'perf record' of selftest 'null_syscall' Christophe Leroy
2021-06-16 3:23 ` Madhavan Srinivasan
2021-06-16 3:40 ` Athira Rajeev
2021-06-16 6:26 ` Christophe Leroy
2021-06-16 6:33 ` Madhavan Srinivasan
2021-06-16 6:48 ` Christophe Leroy
2021-06-17 6:36 ` Athira Rajeev
2021-06-17 16:35 ` Christophe Leroy
2021-06-17 17:51 ` Athira Rajeev
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