INFO: task hung in perf_event_release_kernel

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 3f8a27f9e27b Linux 4.19.211
git tree: linux-4.19.y
console output: https://syzkaller.appspot.com/x/log.txt?x=13d9b02ff00000
kernel config: https://syzkaller.appspot.com/x/.config?x=9b9277b418617afe
dashboard link: https://syzkaller.appspot.com/bug?extid=953f9f094e4e8a58b98f
compiler: gcc version 10.2.1 20210110 (Debian 10.2.1-6)

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+953f9f...@syzkaller.appspotmail.com

ieee802154 phy1 wpan1: encryption failed: -22
ieee802154 phy0 wpan0: encryption failed: -22
ieee802154 phy1 wpan1: encryption failed: -22
ieee802154 phy0 wpan0: encryption failed: -22
ieee802154 phy1 wpan1: encryption failed: -22
INFO: task syz-executor.2:21047 blocked for more than 140 seconds.
Not tainted 4.19.211-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.2 D28648 21047 8161 0x00000004
Call Trace:
context_switch kernel/sched/core.c:2828 [inline]
__schedule+0x887/0x2040 kernel/sched/core.c:3517
schedule+0x8d/0x1b0 kernel/sched/core.c:3561
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3619
__mutex_lock_common kernel/locking/mutex.c:1016 [inline]
__mutex_lock+0x5f0/0x1190 kernel/locking/mutex.c:1078
perf_event_ctx_lock_nested+0x237/0x430 kernel/events/core.c:1283
perf_event_ctx_lock kernel/events/core.c:1296 [inline]
perf_event_release_kernel+0x11c/0xcd0 kernel/events/core.c:4605
perf_release+0x33/0x40 kernel/events/core.c:4703
__fput+0x2ce/0x890 fs/file_table.c:278
task_work_run+0x148/0x1c0 kernel/task_work.c:113
tracehook_notify_resume include/linux/tracehook.h:193 [inline]
exit_to_usermode_loop+0x251/0x2a0 arch/x86/entry/common.c:167
prepare_exit_to_usermode arch/x86/entry/common.c:198 [inline]
syscall_return_slowpath arch/x86/entry/common.c:271 [inline]
do_syscall_64+0x538/0x620 arch/x86/entry/common.c:296
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7f1f5a297d4b
Code: Bad RIP value.
RSP: 002b:00007ffe94addef0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000004 RCX: 00007f1f5a297d4b
RDX: 0000001b31520000 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 00007f1f5a3f9960 R08: 0000000000000000 R09: 0000004a81fa35b9
R10: 000fe8fd35a32f31 R11: 0000000000000293 R12: 000000000004632c
R13: 00007ffe94addff0 R14: 00007ffe94ade010 R15: 0000000000000032
INFO: task syz-executor.2:21056 blocked for more than 140 seconds.
Not tainted 4.19.211-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.2 D29128 21056 8161 0x00000004
Call Trace:
context_switch kernel/sched/core.c:2828 [inline]
__schedule+0x887/0x2040 kernel/sched/core.c:3517
schedule+0x8d/0x1b0 kernel/sched/core.c:3561
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3619
__mutex_lock_common kernel/locking/mutex.c:1016 [inline]
__mutex_lock+0x5f0/0x1190 kernel/locking/mutex.c:1078
mutex_lock_double kernel/events/core.c:10470 [inline]
__perf_event_ctx_lock_double kernel/events/core.c:10529 [inline]
__do_sys_perf_event_open kernel/events/core.c:10784 [inline]
__se_sys_perf_event_open+0x1863/0x2720 kernel/events/core.c:10549
do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7f1f5a2e5109
Code: Bad RIP value.
RSP: 002b:00007f1f58c39168 EFLAGS: 00000246 ORIG_RAX: 000000000000012a
RAX: ffffffffffffffda RBX: 00007f1f5a3f8030 RCX: 00007f1f5a2e5109
RDX: 0000000000000000 RSI: ffffffffffffffff RDI: 0000000020000000
RBP: 00007f1f5a33f0ad R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000046 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffe94adde8f R14: 00007f1f58c39300 R15: 0000000000022000
INFO: task syz-executor.1:21051 blocked for more than 140 seconds.
Not tainted 4.19.211-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.1 D28648 21051 8160 0x00000004
Call Trace:
context_switch kernel/sched/core.c:2828 [inline]
__schedule+0x887/0x2040 kernel/sched/core.c:3517
schedule+0x8d/0x1b0 kernel/sched/core.c:3561
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3619
__mutex_lock_common kernel/locking/mutex.c:1016 [inline]
__mutex_lock+0x5f0/0x1190 kernel/locking/mutex.c:1078
perf_event_ctx_lock_nested+0x237/0x430 kernel/events/core.c:1283
perf_event_ctx_lock kernel/events/core.c:1296 [inline]
perf_event_release_kernel+0x11c/0xcd0 kernel/events/core.c:4605
perf_release+0x33/0x40 kernel/events/core.c:4703
__fput+0x2ce/0x890 fs/file_table.c:278
task_work_run+0x148/0x1c0 kernel/task_work.c:113
tracehook_notify_resume include/linux/tracehook.h:193 [inline]
exit_to_usermode_loop+0x251/0x2a0 arch/x86/entry/common.c:167
prepare_exit_to_usermode arch/x86/entry/common.c:198 [inline]
syscall_return_slowpath arch/x86/entry/common.c:271 [inline]
do_syscall_64+0x538/0x620 arch/x86/entry/common.c:296
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7f1bf2a4fd4b
Code: Bad RIP value.
RSP: 002b:00007fffeab48640 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000004 RCX: 00007f1bf2a4fd4b
RDX: 00007f1bf2bb8ad0 RSI: ffffffffffffffff RDI: 0000000000000003
RBP: 00007f1bf2bb1960 R08: 0000000000000000 R09: 00007f1bf2bb8ad8
R10: 00007fffeab48740 R11: 0000000000000293 R12: 000000000004603e
R13: 00007fffeab48740 R14: 00007f1bf2bb0030 R15: 0000000000000032
INFO: task syz-executor.0:21059 blocked for more than 140 seconds.
Not tainted 4.19.211-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.0 D29736 21059 8157 0x00000004
Call Trace:
context_switch kernel/sched/core.c:2828 [inline]
__schedule+0x887/0x2040 kernel/sched/core.c:3517
schedule+0x8d/0x1b0 kernel/sched/core.c:3561
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3619
__mutex_lock_common kernel/locking/mutex.c:1016 [inline]
__mutex_lock+0x5f0/0x1190 kernel/locking/mutex.c:1078
perf_event_ctx_lock_nested+0x237/0x430 kernel/events/core.c:1283
perf_event_ctx_lock kernel/events/core.c:1296 [inline]
perf_event_release_kernel+0x11c/0xcd0 kernel/events/core.c:4605
perf_release+0x33/0x40 kernel/events/core.c:4703
__fput+0x2ce/0x890 fs/file_table.c:278
task_work_run+0x148/0x1c0 kernel/task_work.c:113
tracehook_notify_resume include/linux/tracehook.h:193 [inline]
exit_to_usermode_loop+0x251/0x2a0 arch/x86/entry/common.c:167
prepare_exit_to_usermode arch/x86/entry/common.c:198 [inline]
syscall_return_slowpath arch/x86/entry/common.c:271 [inline]
do_syscall_64+0x538/0x620 arch/x86/entry/common.c:296
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7f28e987ed4b
Code: Bad RIP value.
RSP: 002b:00007ffec911b920 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000004 RCX: 00007f28e987ed4b
RDX: 00007f28e99e4778 RSI: ffffffffffffffff RDI: 0000000000000003
RBP: 00007f28e99e0960 R08: 0000000000000000 R09: 00007f28e99e4780
R10: 00007ffec911ba20 R11: 0000000000000293 R12: 0000000000046031
R13: 00007ffec911ba20 R14: 00007f28e99def60 R15: 0000000000000032
INFO: task syz-executor.3:21067 blocked for more than 140 seconds.
Not tainted 4.19.211-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.3 D27736 21067 8158 0x00000004
Call Trace:
context_switch kernel/sched/core.c:2828 [inline]
__schedule+0x887/0x2040 kernel/sched/core.c:3517
schedule+0x8d/0x1b0 kernel/sched/core.c:3561
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3619
__mutex_lock_common kernel/locking/mutex.c:1016 [inline]
__mutex_lock+0x5f0/0x1190 kernel/locking/mutex.c:1078
__do_sys_perf_event_open kernel/events/core.c:10822 [inline]
__se_sys_perf_event_open+0xaf7/0x2720 kernel/events/core.c:10549
do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7f6ca5fac109
Code: Bad RIP value.
RSP: 002b:00007f6ca4921168 EFLAGS: 00000246 ORIG_RAX: 000000000000012a
RAX: ffffffffffffffda RBX: 00007f6ca60bef60 RCX: 00007f6ca5fac109
RDX: 0000000000000000 RSI: ffffffffffffffff RDI: 0000000020000000
RBP: 00007f6ca60060ad R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000005 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fff68ba874f R14: 00007f6ca4921300 R15: 0000000000022000
INFO: task syz-executor.3:21071 blocked for more than 140 seconds.
Not tainted 4.19.211-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.3 D27736 21071 8158 0x00000004
Call Trace:
context_switch kernel/sched/core.c:2828 [inline]
__schedule+0x887/0x2040 kernel/sched/core.c:3517
schedule+0x8d/0x1b0 kernel/sched/core.c:3561
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3619
__mutex_lock_common kernel/locking/mutex.c:1016 [inline]
__mutex_lock+0x5f0/0x1190 kernel/locking/mutex.c:1078
__do_sys_perf_event_open kernel/events/core.c:10822 [inline]
__se_sys_perf_event_open+0xaf7/0x2720 kernel/events/core.c:10549
do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7f6ca5fac109
Code: Bad RIP value.
RSP: 002b:00007f6ca4900168 EFLAGS: 00000246 ORIG_RAX: 000000000000012a
RAX: ffffffffffffffda RBX: 00007f6ca60bf030 RCX: 00007f6ca5fac109
RDX: 0000000000000000 RSI: ffffffffffffffff RDI: 0000000020000000
RBP: 00007f6ca60060ad R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000005 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fff68ba874f R14: 00007f6ca4900300 R15: 0000000000022000
INFO: task syz-executor.3:21074 blocked for more than 140 seconds.
Not tainted 4.19.211-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.3 D29984 21074 8158 0x00000004
Call Trace:
context_switch kernel/sched/core.c:2828 [inline]
__schedule+0x887/0x2040 kernel/sched/core.c:3517
schedule+0x8d/0x1b0 kernel/sched/core.c:3561
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3619
__mutex_lock_common kernel/locking/mutex.c:1016 [inline]
__mutex_lock+0x5f0/0x1190 kernel/locking/mutex.c:1078
__do_sys_perf_event_open kernel/events/core.c:10822 [inline]
__se_sys_perf_event_open+0xaf7/0x2720 kernel/events/core.c:10549
do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7f6ca5fac109
Code: Bad RIP value.
RSP: 002b:00007f6ca489d168 EFLAGS: 00000246 ORIG_RAX: 000000000000012a
RAX: ffffffffffffffda RBX: 00007f6ca60bf2a0 RCX: 00007f6ca5fac109
RDX: 0000000000000000 RSI: ffffffffffffffff RDI: 0000000020000000
RBP: 00007f6ca60060ad R08: 0000000000000000 R09: 0000000000000000
R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000
R13: 00007fff68ba874f R14: 00007f6ca489d300 R15: 0000000000022000
INFO: task syz-executor.5:21070 blocked for more than 140 seconds.
Not tainted 4.19.211-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.5 D29736 21070 8159 0x00000004
Call Trace:
context_switch kernel/sched/core.c:2828 [inline]
__schedule+0x887/0x2040 kernel/sched/core.c:3517
schedule+0x8d/0x1b0 kernel/sched/core.c:3561
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3619
__mutex_lock_common kernel/locking/mutex.c:1016 [inline]
__mutex_lock+0x5f0/0x1190 kernel/locking/mutex.c:1078
__do_sys_perf_event_open kernel/events/core.c:10822 [inline]
__se_sys_perf_event_open+0xaf7/0x2720 kernel/events/core.c:10549
do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7fe436e68109
Code: Bad RIP value.
RSP: 002b:00007fe4357dd168 EFLAGS: 00000246 ORIG_RAX: 000000000000012a
RAX: ffffffffffffffda RBX: 00007fe436f7af60 RCX: 00007fe436e68109
RDX: 0000000000000000 RSI: ffffffffffffffff RDI: 0000000020000000
RBP: 00007fe436ec20ad R08: 0000000000000000 R09: 0000000000000000
R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffd2546982f R14: 00007fe4357dd300 R15: 0000000000022000
INFO: task syz-executor.5:21078 blocked for more than 140 seconds.
Not tainted 4.19.211-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.5 D29984 21078 8159 0x00000004
Call Trace:
context_switch kernel/sched/core.c:2828 [inline]
__schedule+0x887/0x2040 kernel/sched/core.c:3517
schedule+0x8d/0x1b0 kernel/sched/core.c:3561
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3619
__mutex_lock_common kernel/locking/mutex.c:1016 [inline]
__mutex_lock+0x5f0/0x1190 kernel/locking/mutex.c:1078
__do_sys_perf_event_open kernel/events/core.c:10822 [inline]
__se_sys_perf_event_open+0xaf7/0x2720 kernel/events/core.c:10549
do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7fe436e68109
Code: Bad RIP value.
RSP: 002b:00007fe4357bc168 EFLAGS: 00000246 ORIG_RAX: 000000000000012a
RAX: ffffffffffffffda RBX: 00007fe436f7b030 RCX: 00007fe436e68109
RDX: 0000000000000000 RSI: ffffffffffffffff RDI: 0000000020000000
RBP: 00007fe436ec20ad R08: 0000000000000000 R09: 0000000000000000
R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffd2546982f R14: 00007fe4357bc300 R15: 0000000000022000
INFO: task syz-executor.5:21079 blocked for more than 140 seconds.
Not tainted 4.19.211-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.5 D29432 21079 8159 0x00000004
Call Trace:
context_switch kernel/sched/core.c:2828 [inline]
__schedule+0x887/0x2040 kernel/sched/core.c:3517
schedule+0x8d/0x1b0 kernel/sched/core.c:3561
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3619
__mutex_lock_common kernel/locking/mutex.c:1016 [inline]
__mutex_lock+0x5f0/0x1190 kernel/locking/mutex.c:1078
__do_sys_perf_event_open kernel/events/core.c:10822 [inline]
__se_sys_perf_event_open+0xaf7/0x2720 kernel/events/core.c:10549
do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7fe436e68109
Code: Bad RIP value.
RSP: 002b:00007fe43579b168 EFLAGS: 00000246 ORIG_RAX: 000000000000012a
RAX: ffffffffffffffda RBX: 00007fe436f7b100 RCX: 00007fe436e68109
RDX: 0000000000000000 RSI: ffffffffffffffff RDI: 0000000020000000
RBP: 00007fe436ec20ad R08: 0000000000000000 R09: 0000000000000000
R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffd2546982f R14: 00007fe43579b300 R15: 0000000000022000

Showing all locks held in the system:
1 lock held by khungtaskd/1569:
#0: 0000000086eae520 (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x265 kernel/locking/lockdep.c:4441
1 lock held by in:imklog/7839:
#0: 00000000f6c45897 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x26f/0x310 fs/file.c:767
1 lock held by syz-executor.2/21047:
#0: 000000001155a01e (&cpuctx_mutex){+.+.}, at: perf_event_ctx_lock_nested+0x237/0x430 kernel/events/core.c:1283
2 locks held by syz-executor.2/21056:
#0: 000000002ff8bd1d (&cpuctx_mutex){+.+.}, at: mutex_lock_double kernel/events/core.c:10469 [inline]
#0: 000000002ff8bd1d (&cpuctx_mutex){+.+.}, at: __perf_event_ctx_lock_double kernel/events/core.c:10529 [inline]
#0: 000000002ff8bd1d (&cpuctx_mutex){+.+.}, at: __do_sys_perf_event_open kernel/events/core.c:10784 [inline]
#0: 000000002ff8bd1d (&cpuctx_mutex){+.+.}, at: __se_sys_perf_event_open+0x1856/0x2720 kernel/events/core.c:10549
#1: 000000002ff8bd1d (&cpuctx_mutex/1){+.+.}, at: mutex_lock_double kernel/events/core.c:10470 [inline]
#1: 000000002ff8bd1d (&cpuctx_mutex/1){+.+.}, at: __perf_event_ctx_lock_double kernel/events/core.c:10529 [inline]
#1: 000000002ff8bd1d (&cpuctx_mutex/1){+.+.}, at: __do_sys_perf_event_open kernel/events/core.c:10784 [inline]
#1: 000000002ff8bd1d (&cpuctx_mutex/1){+.+.}, at: __se_sys_perf_event_open+0x1863/0x2720 kernel/events/core.c:10549
1 lock held by syz-executor.1/21051:
#0: 000000002ff8bd1d (&cpuctx_mutex){+.+.}, at: perf_event_ctx_lock_nested+0x237/0x430 kernel/events/core.c:1283
1 lock held by syz-executor.0/21059:
#0: 000000002ff8bd1d (&cpuctx_mutex){+.+.}, at: perf_event_ctx_lock_nested+0x237/0x430 kernel/events/core.c:1283
1 lock held by syz-executor.3/21067:
#0: 000000002ff8bd1d (&cpuctx_mutex){+.+.}, at: __do_sys_perf_event_open kernel/events/core.c:10822 [inline]
#0: 000000002ff8bd1d (&cpuctx_mutex){+.+.}, at: __se_sys_perf_event_open+0xaf7/0x2720 kernel/events/core.c:10549
1 lock held by syz-executor.3/21071:
#0: 000000002ff8bd1d (&cpuctx_mutex){+.+.}, at: __do_sys_perf_event_open kernel/events/core.c:10822 [inline]
#0: 000000002ff8bd1d (&cpuctx_mutex){+.+.}, at: __se_sys_perf_event_open+0xaf7/0x2720 kernel/events/core.c:10549
1 lock held by syz-executor.3/21074:
#0: 000000002ff8bd1d (&cpuctx_mutex){+.+.}, at: __do_sys_perf_event_open kernel/events/core.c:10822 [inline]
#0: 000000002ff8bd1d (&cpuctx_mutex){+.+.}, at: __se_sys_perf_event_open+0xaf7/0x2720 kernel/events/core.c:10549
1 lock held by syz-executor.5/21070:
#0: 000000001155a01e (&cpuctx_mutex){+.+.}, at: __do_sys_perf_event_open kernel/events/core.c:10822 [inline]
#0: 000000001155a01e (&cpuctx_mutex){+.+.}, at: __se_sys_perf_event_open+0xaf7/0x2720 kernel/events/core.c:10549
1 lock held by syz-executor.5/21078:
#0: 000000002ff8bd1d (&cpuctx_mutex){+.+.}, at: __do_sys_perf_event_open kernel/events/core.c:10822 [inline]
#0: 000000002ff8bd1d (&cpuctx_mutex){+.+.}, at: __se_sys_perf_event_open+0xaf7/0x2720 kernel/events/core.c:10549
1 lock held by syz-executor.5/21079:
#0: 000000002ff8bd1d (&cpuctx_mutex){+.+.}, at: __do_sys_perf_event_open kernel/events/core.c:10822 [inline]
#0: 000000002ff8bd1d (&cpuctx_mutex){+.+.}, at: __se_sys_perf_event_open+0xaf7/0x2720 kernel/events/core.c:10549
1 lock held by syz-executor.5/21080:
#0: 000000002ff8bd1d (&cpuctx_mutex){+.+.}, at: __do_sys_perf_event_open kernel/events/core.c:10822 [inline]
#0: 000000002ff8bd1d (&cpuctx_mutex){+.+.}, at: __se_sys_perf_event_open+0xaf7/0x2720 kernel/events/core.c:10549
2 locks held by syz-executor.4/21069:
#0: 000000001155a01e (&cpuctx_mutex){+.+.}, at: mutex_lock_double kernel/events/core.c:10469 [inline]
#0: 000000001155a01e (&cpuctx_mutex){+.+.}, at: __perf_event_ctx_lock_double kernel/events/core.c:10529 [inline]
#0: 000000001155a01e (&cpuctx_mutex){+.+.}, at: __do_sys_perf_event_open kernel/events/core.c:10784 [inline]
#0: 000000001155a01e (&cpuctx_mutex){+.+.}, at: __se_sys_perf_event_open+0x1856/0x2720 kernel/events/core.c:10549
#1: 000000002ff8bd1d (&cpuctx_mutex/1){+.+.}, at: mutex_lock_double kernel/events/core.c:10470 [inline]
#1: 000000002ff8bd1d (&cpuctx_mutex/1){+.+.}, at: __perf_event_ctx_lock_double kernel/events/core.c:10529 [inline]
#1: 000000002ff8bd1d (&cpuctx_mutex/1){+.+.}, at: __do_sys_perf_event_open kernel/events/core.c:10784 [inline]
#1: 000000002ff8bd1d (&cpuctx_mutex/1){+.+.}, at: __se_sys_perf_event_open+0x1863/0x2720 kernel/events/core.c:10549

=============================================

NMI backtrace for cpu 0
CPU: 0 PID: 1569 Comm: khungtaskd Not tainted 4.19.211-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x1fc/0x2ef lib/dump_stack.c:118
nmi_cpu_backtrace.cold+0x63/0xa2 lib/nmi_backtrace.c:101
nmi_trigger_cpumask_backtrace+0x1a6/0x1f0 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:203 [inline]
watchdog+0x991/0xe60 kernel/hung_task.c:287
kthread+0x33f/0x460 kernel/kthread.c:259
ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 18 Comm: ksoftirqd/1 Not tainted 4.19.211-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:rcu_cblist_dequeue+0x60/0xe0 kernel/rcu/rcu_segcblist.c:54
Code: fc ff df 48 89 f9 48 c1 e9 03 80 3c 11 00 75 64 48 ba 00 00 00 00 00 fc ff df 48 89 c1 48 83 6b 10 01 48 c1 e9 03 80 3c 11 00 <75> 36 48 8b 10 48 85 d2 48 89 13 74 06 48 83 c4 08 5b c3 48 8d 7b
RSP: 0018:ffff8880b5acfcd0 EFLAGS: 00000246
RAX: ffff8880a9d29d40 RBX: ffff8880b5acfd60 RCX: 1ffff110153a53a8
RDX: dffffc0000000000 RSI: 0000000000000001 RDI: ffff8880b5acfd70
RBP: ffffffff81a31cc0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff88809de52ac8
R13: ffff8880b5acfd60 R14: 000000000000000a R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff8880ba100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f48650db008 CR3: 00000000a136f000 CR4: 00000000003406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 00000000b8fecd19 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
rcu_do_batch kernel/rcu/tree.c:2582 [inline]
invoke_rcu_callbacks kernel/rcu/tree.c:2897 [inline]
__rcu_process_callbacks kernel/rcu/tree.c:2864 [inline]
rcu_process_callbacks+0x989/0x18b0 kernel/rcu/tree.c:2881
__do_softirq+0x265/0x980 kernel/softirq.c:292
run_ksoftirqd+0x57/0x110 kernel/softirq.c:653
smpboot_thread_fn+0x655/0x9e0 kernel/smpboot.c:164
kthread+0x33f/0x460 kernel/kthread.c:259
ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415
----------------
Code disassembly (best guess), 2 bytes skipped:
0: df 48 89 fisttps -0x77(%rax)
3: f9 stc
4: 48 c1 e9 03 shr $0x3,%rcx
8: 80 3c 11 00 cmpb $0x0,(%rcx,%rdx,1)
c: 75 64 jne 0x72
e: 48 ba 00 00 00 00 00 movabs $0xdffffc0000000000,%rdx
15: fc ff df
18: 48 89 c1 mov %rax,%rcx
1b: 48 83 6b 10 01 subq $0x1,0x10(%rbx)
20: 48 c1 e9 03 shr $0x3,%rcx
24: 80 3c 11 00 cmpb $0x0,(%rcx,%rdx,1)
* 28: 75 36 jne 0x60 <-- trapping instruction
2a: 48 8b 10 mov (%rax),%rdx
2d: 48 85 d2 test %rdx,%rdx
30: 48 89 13 mov %rdx,(%rbx)
33: 74 06 je 0x3b
35: 48 83 c4 08 add $0x8,%rsp
39: 5b pop %rbx
3a: c3 retq
3b: 48 rex.W
3c: 8d .byte 0x8d
3d: 7b .byte 0x7b


---
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[syzbot]

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