[syzbot] WARNING in __perf_install_in_context

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 18a3c5f7 Merge tag 'for_linus' of git://git.kernel.org/pub..
git tree: git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux.git fixes
console output: https://syzkaller.appspot.com/x/log.txt?x=1662c153d00000
kernel config: https://syzkaller.appspot.com/x/.config?x=b8ac1fe5995f69d7
dashboard link: https://syzkaller.appspot.com/bug?extid=0fb24f56fa707081e4f2
userspace arch: riscv64

Unfortunately, I don't have any reproducer for this issue yet.

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+0fb24f...@syzkaller.appspotmail.com

------------[ cut here ]------------
WARNING: CPU: 1 PID: 8643 at kernel/events/core.c:2781 __perf_install_in_context+0x1c0/0x47c kernel/events/core.c:2781
Modules linked in:
CPU: 1 PID: 8643 Comm: syz-executor.0 Not tainted 5.12.0-rc8-syzkaller-00011-g18a3c5f7abfd #0
Hardware name: riscv-virtio,qemu (DT)
epc : __perf_install_in_context+0x1c0/0x47c kernel/events/core.c:2781
ra : __perf_install_in_context+0x1c0/0x47c kernel/events/core.c:2781
epc : ffffffe00027d7ba ra : ffffffe00027d7ba sp : ffffffe00818faf0
gp : ffffffe0045883c0 tp : ffffffe006dbaf80 t0 : ffffffc4010812b2
t1 : 0000000000000001 t2 : 0000000000000000 s0 : ffffffe00818fb50
s1 : ffffffe01ca95000 a0 : ffffffe066d79118 a1 : 00000000000f0000
a2 : ffffffd010ada000 a3 : ffffffe00027d7ba a4 : ffffffd010ae31f0
a5 : 000000000000123e a6 : 0000000000f00000 a7 : ffffffe00027d6ba
s2 : ffffffe066d78f70 s3 : ffffffe01ca950a8 s4 : ffffffe00aacfc00
s5 : ffffffe006dbaf80 s6 : ffffffe066d78f78 s7 : ffffffe00d98bc00
s8 : ffffffe006dbaf80 s9 : ffffffe00458c0d0 s10: 0000000000000000
s11: 0000000000000000 t3 : 2699545dc3e5be00 t4 : ffffffc401031f97
t5 : ffffffc401031f99 t6 : ffffffe00f58c1f4
status: 0000000000000100 badaddr: 0000000000000000 cause: 0000000000000003
Call Trace:
[<ffffffe00027d7ba>] __perf_install_in_context+0x1c0/0x47c kernel/events/core.c:2781
[<ffffffe00026bcbc>] remote_function kernel/events/core.c:91 [inline]
[<ffffffe00026bcbc>] remote_function+0xa8/0xc0 kernel/events/core.c:71
[<ffffffe0001452b2>] generic_exec_single+0x1a6/0x212 kernel/smp.c:293
[<ffffffe000145452>] smp_call_function_single+0x134/0x2ba kernel/smp.c:513
[<ffffffe00026af46>] task_function_call+0x90/0xee kernel/events/core.c:119
[<ffffffe00027c5da>] perf_install_in_context+0x174/0x2e6 kernel/events/core.c:2902
[<ffffffe000288d1c>] __do_sys_perf_event_open+0x10ea/0x199e kernel/events/core.c:12169
[<ffffffe00028fa72>] sys_perf_event_open+0x34/0x46 kernel/events/core.c:11775
[<ffffffe000005578>] ret_from_syscall+0x0/0x2
irq event stamp: 1944
hardirqs last enabled at (1943): [<ffffffe0003b3950>] mod_memcg_lruvec_state include/linux/memcontrol.h:979 [inline]
hardirqs last enabled at (1943): [<ffffffe0003b3950>] mod_objcg_state mm/slab.h:296 [inline]
hardirqs last enabled at (1943): [<ffffffe0003b3950>] memcg_slab_post_alloc_hook+0x2ea/0x46a mm/slab.h:327
hardirqs last disabled at (1944): [<ffffffe0001452ae>] generic_exec_single+0x1a2/0x212 kernel/smp.c:292
softirqs last enabled at (1900): [<ffffffe0020f5fd2>] spin_unlock_bh include/linux/spinlock.h:399 [inline]
softirqs last enabled at (1900): [<ffffffe0020f5fd2>] release_sock+0xf6/0x122 net/core/sock.c:3085
softirqs last disabled at (1898): [<ffffffe0020f5f06>] spin_lock_bh include/linux/spinlock.h:359 [inline]
softirqs last disabled at (1898): [<ffffffe0020f5f06>] release_sock+0x2a/0x122 net/core/sock.c:3072
---[ end trace 757ee55d225523fe ]---
------------[ cut here ]------------
WARNING: CPU: 1 PID: 8643 at kernel/events/core.c:3210 ctx_sched_out+0x312/0x548 kernel/events/core.c:3210
Modules linked in:
CPU: 1 PID: 8643 Comm: syz-executor.0 Tainted: G W 5.12.0-rc8-syzkaller-00011-g18a3c5f7abfd #0
Hardware name: riscv-virtio,qemu (DT)
epc : ctx_sched_out+0x312/0x548 kernel/events/core.c:3210
ra : ctx_sched_out+0x312/0x548 kernel/events/core.c:3210
epc : ffffffe00027ca5e ra : ffffffe00027ca5e sp : ffffffe00818fa90
gp : ffffffe0045883c0 tp : ffffffe006dbaf80 t0 : ffffffc4010812b2
t1 : 0000000000000001 t2 : 0000000000000000 s0 : ffffffe00818faf0
s1 : ffffffe00aacfc00 a0 : ffffffe066d79118 a1 : 00000000000f0000
a2 : ffffffd010ada000 a3 : ffffffe00027ca5e a4 : ffffffd010c9c740
a5 : 00000000000384e8 a6 : 0000000000f00000 a7 : ffffffe00027d6ba
s2 : ffffffe066d78f70 s3 : 0000000000000004 s4 : 0000000000000000
s5 : 0000000000000000 s6 : ffffffe00aacfd40 s7 : 0000000000000000
s8 : ffffffe006dbaf80 s9 : ffffffe00458c0d0 s10: 0000000000000000
s11: 0000000000000000 t3 : 2699545dc3e5be00 t4 : ffffffc401031f97
t5 : ffffffc401031f99 t6 : ffffffe00f58c1f4
status: 0000000000000100 badaddr: 0000000000000000 cause: 0000000000000003
Call Trace:
[<ffffffe00027ca5e>] ctx_sched_out+0x312/0x548 kernel/events/core.c:3210
[<ffffffe00027d7ee>] __perf_install_in_context+0x1f4/0x47c kernel/events/core.c:2799
[<ffffffe00026bcbc>] remote_function kernel/events/core.c:91 [inline]
[<ffffffe00026bcbc>] remote_function+0xa8/0xc0 kernel/events/core.c:71
[<ffffffe0001452b2>] generic_exec_single+0x1a6/0x212 kernel/smp.c:293
[<ffffffe000145452>] smp_call_function_single+0x134/0x2ba kernel/smp.c:513
[<ffffffe00026af46>] task_function_call+0x90/0xee kernel/events/core.c:119
[<ffffffe00027c5da>] perf_install_in_context+0x174/0x2e6 kernel/events/core.c:2902
[<ffffffe000288d1c>] __do_sys_perf_event_open+0x10ea/0x199e kernel/events/core.c:12169
[<ffffffe00028fa72>] sys_perf_event_open+0x34/0x46 kernel/events/core.c:11775
[<ffffffe000005578>] ret_from_syscall+0x0/0x2
irq event stamp: 1944
hardirqs last enabled at (1943): [<ffffffe0003b3950>] mod_memcg_lruvec_state include/linux/memcontrol.h:979 [inline]
hardirqs last enabled at (1943): [<ffffffe0003b3950>] mod_objcg_state mm/slab.h:296 [inline]
hardirqs last enabled at (1943): [<ffffffe0003b3950>] memcg_slab_post_alloc_hook+0x2ea/0x46a mm/slab.h:327
hardirqs last disabled at (1944): [<ffffffe0001452ae>] generic_exec_single+0x1a2/0x212 kernel/smp.c:292
softirqs last enabled at (1900): [<ffffffe0020f5fd2>] spin_unlock_bh include/linux/spinlock.h:399 [inline]
softirqs last enabled at (1900): [<ffffffe0020f5fd2>] release_sock+0xf6/0x122 net/core/sock.c:3085
softirqs last disabled at (1898): [<ffffffe0020f5f06>] spin_lock_bh include/linux/spinlock.h:359 [inline]
softirqs last disabled at (1898): [<ffffffe0020f5f06>] release_sock+0x2a/0x122 net/core/sock.c:3072
---[ end trace 757ee55d225523ff ]---
------------[ cut here ]------------
WARNING: CPU: 1 PID: 8643 at kernel/events/core.c:2668 task_ctx_sched_out+0x5c/0x60 kernel/events/core.c:2668
Modules linked in:
CPU: 1 PID: 8643 Comm: syz-executor.0 Tainted: G W 5.12.0-rc8-syzkaller-00011-g18a3c5f7abfd #0
Hardware name: riscv-virtio,qemu (DT)
epc : task_ctx_sched_out+0x5c/0x60 kernel/events/core.c:2668
ra : task_ctx_sched_out+0x5c/0x60 kernel/events/core.c:2668
epc : ffffffe00027ccf0 ra : ffffffe00027ccf0 sp : ffffffe00818fa70
gp : ffffffe0045883c0 tp : ffffffe006dbaf80 t0 : ffffffc4010812b2
t1 : 0000000000000001 t2 : 0000000000000000 s0 : ffffffe00818faa0
s1 : ffffffe066d78f70 a0 : ffffffe066d79118 a1 : 00000000000f0000
a2 : ffffffd010ada000 a3 : ffffffe00027ccf0 a4 : 0000000000040000
a5 : 0000000000040000 a6 : 0000000000f00000 a7 : ffffffe00027d6ba
s2 : ffffffe00aacfc00 s3 : 0000000000000001 s4 : ffffffe00d98bc00
s5 : ffffffe0050495a8 s6 : ffffffe00aacfc00 s7 : ffffffe00423cdc8
s8 : 0000000000000000 s9 : ffffffe00458c0d0 s10: 0000000000000000
s11: 0000000000000000 t3 : 2699545dc3e5be00 t4 : ffffffc401031f97
t5 : ffffffc401031f99 t6 : ffffffe00f58c1f4
status: 0000000000000100 badaddr: 0000000000000000 cause: 0000000000000003
Call Trace:
[<ffffffe00027ccf0>] task_ctx_sched_out+0x5c/0x60 kernel/events/core.c:2668
[<ffffffe00027cdca>] ctx_resched+0xd6/0x1ba kernel/events/core.c:2719
[<ffffffe00027d80e>] __perf_install_in_context+0x214/0x47c kernel/events/core.c:2801
[<ffffffe00026bcbc>] remote_function kernel/events/core.c:91 [inline]
[<ffffffe00026bcbc>] remote_function+0xa8/0xc0 kernel/events/core.c:71
[<ffffffe0001452b2>] generic_exec_single+0x1a6/0x212 kernel/smp.c:293
[<ffffffe000145452>] smp_call_function_single+0x134/0x2ba kernel/smp.c:513
[<ffffffe00026af46>] task_function_call+0x90/0xee kernel/events/core.c:119
[<ffffffe00027c5da>] perf_install_in_context+0x174/0x2e6 kernel/events/core.c:2902
[<ffffffe000288d1c>] __do_sys_perf_event_open+0x10ea/0x199e kernel/events/core.c:12169
[<ffffffe00028fa72>] sys_perf_event_open+0x34/0x46 kernel/events/core.c:11775
[<ffffffe000005578>] ret_from_syscall+0x0/0x2
irq event stamp: 1944
hardirqs last enabled at (1943): [<ffffffe0003b3950>] mod_memcg_lruvec_state include/linux/memcontrol.h:979 [inline]
hardirqs last enabled at (1943): [<ffffffe0003b3950>] mod_objcg_state mm/slab.h:296 [inline]
hardirqs last enabled at (1943): [<ffffffe0003b3950>] memcg_slab_post_alloc_hook+0x2ea/0x46a mm/slab.h:327
hardirqs last disabled at (1944): [<ffffffe0001452ae>] generic_exec_single+0x1a2/0x212 kernel/smp.c:292
softirqs last enabled at (1900): [<ffffffe0020f5fd2>] spin_unlock_bh include/linux/spinlock.h:399 [inline]
softirqs last enabled at (1900): [<ffffffe0020f5fd2>] release_sock+0xf6/0x122 net/core/sock.c:3085
softirqs last disabled at (1898): [<ffffffe0020f5f06>] spin_lock_bh include/linux/spinlock.h:359 [inline]
softirqs last disabled at (1898): [<ffffffe0020f5f06>] release_sock+0x2a/0x122 net/core/sock.c:3072
---[ end trace 757ee55d22552400 ]---


---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzk...@googlegroups.com.

syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.

[Peter Zijlstra]

On Mon, May 17, 2021 at 03:56:22AM -0700, syzbot wrote:
> Hello,
>
> syzbot found the following issue on:
>
> HEAD commit: 18a3c5f7 Merge tag 'for_linus' of git://git.kernel.org/pub..
> git tree: git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux.git fixes
> console output: https://syzkaller.appspot.com/x/log.txt?x=1662c153d00000
> kernel config: https://syzkaller.appspot.com/x/.config?x=b8ac1fe5995f69d7
> dashboard link: https://syzkaller.appspot.com/bug?extid=0fb24f56fa707081e4f2
> userspace arch: riscv64
>
> Unfortunately, I don't have any reproducer for this issue yet.
>
> IMPORTANT: if you fix the issue, please add the following tag to the commit:
> Reported-by: syzbot+0fb24f...@syzkaller.appspotmail.com
>
> ------------[ cut here ]------------
> WARNING: CPU: 1 PID: 8643 at kernel/events/core.c:2781 __perf_install_in_context+0x1c0/0x47c kernel/events/core.c:2781
> Modules linked in:
> CPU: 1 PID: 8643 Comm: syz-executor.0 Not tainted 5.12.0-rc8-syzkaller-00011-g18a3c5f7abfd #0
> Hardware name: riscv-virtio,qemu (DT)

How serious should I take this thing? ARM64 and x86_64 don't show these
errors.

[Dmitry Vyukov]

+riscv mainters for this question
Is perf on riscv considered stable?

[Dmitry Vyukov]

Another perf/riscv64 warning just come in:
https://syzkaller.appspot.com/bug?extid=30189c98403be62bc05a

[Mark Rutland]

I think I've seen this in the past on arm64, but very rarely, and never
with a consistent reproducer.

I'm currently fuyzzing v5.13-rc1, and haven't hit anything like this
after ~5 days.

Thanks,
Mark.

[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.