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INFO: rcu detected stall in perf_release

Status: auto-obsoleted due to no activity on 2024/12/25 21:00
Reported-by: syzbot+2b829c0471de9343c1fd@syzkaller.appspotmail.com
First crash: 499d, last: 499d
▶ ▼ Similar bugs (7)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.6 INFO: rcu detected stall in perf_release (2) origin:lts-only 1 C error 1 26d 26d 0/2 upstream: reported C repro on 2026/01/03 14:19
linux-5.15 INFO: rcu detected stall in perf_release origin:lts-only 1 syz error 2 36d 88d 0/3 upstream: reported syz repro on 2025/11/02 03:41
linux-6.1 INFO: rcu detected stall in perf_release (2) 1 C inconclusive 3 63d 113d 0/3 upstream: reported C repro on 2025/10/08 16:52
linux-6.6 INFO: rcu detected stall in perf_release 1 C done 1 154d 154d 2/2 fixed on 2025/10/06 10:09
upstream INFO: rcu detected stall in perf_release mm cgroups 1 19 2248d 2269d 0/29 auto-closed as invalid on 2020/03/03 09:44
android-5-15 BUG: soft lockup in perf_release (2) 1 1 306d 306d 0/2 auto-obsoleted due to no activity on 2025/06/27 12:18
android-5-15 BUG: soft lockup in perf_release 1 3 587d 649d 0/2 auto-obsoleted due to no activity on 2024/09/19 17:30

Sample crash report:
rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	0-....: (1841 ticks this GP) idle=d2a4/1/0x4000000000000000 softirq=14925/14926 fqs=59
	(t=10500 jiffies g=16129 q=1377 ncpus=2)
rcu: rcu_preempt kthread starved for 287 jiffies! g16129 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
rcu: 	Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt     state:I stack:26712 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5241 [inline]
 __schedule+0x143f/0x4570 kernel/sched/core.c:6558
 schedule+0xbf/0x180 kernel/sched/core.c:6634
 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1965
 rcu_gp_fqs_loop+0x2d2/0x1150 kernel/rcu/tree.c:1706
 rcu_gp_kthread+0xa3/0x3b0 kernel/rcu/tree.c:1905
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 4622 Comm: syz.4.122 Not tainted 6.1.110-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
RIP: 0010:asm_exc_int3+0x0/0x40 arch/x86/include/asm/idtentry.h:568
Code: 00 66 0f 1f 84 00 00 00 00 00 0f 01 ca fc 6a ff e8 35 06 00 00 48 89 c4 48 89 e7 e8 ba 90 e6 ff e9 15 07 00 00 0f 1f 44 00 00 <0f> 01 ca fc 6a ff f6 44 24 10 03 75 18 ff 74 24 28 ff 74 24 28 ff
RSP: 0018:ffffc900001e0898 EFLAGS: 00000806
RAX: f3f3f3f3f300f2f2 RBX: 0000000000000046 RCX: ffffffff816b3d32
RDX: dffffc0000000000 RSI: ffffffff817a2a5f RDI: ffffffff8d344108
RBP: ffffc900001e09f0 R08: dffffc0000000000 R09: fffffbfff223b846
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff9200003c124
R13: ffffffff817a2a5f R14: ffffc900001e0a20 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f9da5136018 CR3: 00000000659c1000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
RIP: 0010:arch_static_branch arch/x86/include/asm/jump_label.h:27 [inline]
RIP: 0010:static_key_false include/linux/jump_label.h:207 [inline]
RIP: 0010:trace_lock_release include/trace/events/lock.h:69 [inline]
RIP: 0010:lock_release+0x7d/0xa20 kernel/locking/lockdep.c:5673
Code: a9 6a 81 4c 8d 64 24 60 49 c1 ec 03 48 b8 f1 f1 f1 f1 04 f2 00 f2 4b 89 04 3c 48 b8 f2 f2 00 f3 f3 f3 f3 f3 4b 89 44 3c 08 cc <42> 08 00 00 65 8b 1d c8 6f 97 7e 48 c7 c0 b8 e6 99 8e 48 c1 e8 03
RSP: 0018:ffffc900001e08c0 EFLAGS: 00000806
 </IRQ>
 <TASK>
 </TASK>
CPU: 0 PID: 4620 Comm: syz.0.121 Not tainted 6.1.110-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
RIP: 0010:trace_lock_release include/trace/events/lock.h:69 [inline]
RIP: 0010:lock_release+0x81/0xa20 kernel/locking/lockdep.c:5673
Code: 8d 64 24 60 49 c1 ec 03 48 b8 f1 f1 f1 f1 04 f2 00 f2 4b 89 04 3c 48 b8 f2 f2 00 f3 f3 f3 f3 f3 4b 89 44 3c 08 cc 42 08 00 00 <65> 8b 1d c8 6f 97 7e 48 c7 c0 b8 e6 99 8e 48 c1 e8 03 42 0f b6 04
RSP: 0018:ffffc90000007920 EFLAGS: 00000a06
RAX: f3f3f3f3f300f2f2 RBX: 0000000000000000 RCX: ffffffff816af0fa
RDX: dffffc0000000000 RSI: ffffffff8960a9c8 RDI: ffffffff8d32b000
RBP: ffffc90000007a48 R08: dffffc0000000000 R09: fffffbfff223b863
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff92000000f30
R13: ffffffff8960a9c8 R14: dffffc0000000000 R15: dffffc0000000000
FS:  00007ff90df206c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2e11aff8 CR3: 0000000058b40000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 rcu_lock_release include/linux/rcupdate.h:355 [inline]
 rcu_read_unlock include/linux/rcupdate.h:824 [inline]
 ipv6_get_lladdr+0x356/0x3c0 net/ipv6/addrconf.c:1896
 addrconf_rs_timer+0x25d/0x610 net/ipv6/addrconf.c:3962
 call_timer_fn+0x1ad/0x6b0 kernel/time/timer.c:1504
 expire_timers kernel/time/timer.c:1549 [inline]
 __run_timers+0x67c/0x890 kernel/time/timer.c:1820
 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1833
 handle_softirqs+0x2ee/0xa40 kernel/softirq.c:571
 __do_softirq kernel/softirq.c:605 [inline]
 invoke_softirq kernel/softirq.c:445 [inline]
 __irq_exit_rcu+0x157/0x240 kernel/softirq.c:654
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:666
 sysvec_apic_timer_interrupt+0x91/0xb0 arch/x86/kernel/apic/apic.c:1106
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:653
RIP: 0010:lock_release+0x65f/0xa20 kernel/locking/lockdep.c:5686
Code: e0 45 4b c7 04 27 00 00 00 00 4b c7 44 27 08 00 00 00 00 65 48 8b 04 25 28 00 00 00 48 3b 84 24 e0 00 00 00 0f 85 5f 03 00 00 <48> 8d 65 d8 5b 41 5c 41 5d 41 5e 41 5f 5d c3 0f 0b e9 37 fa ff ff
RSP: 0018:ffffc9000382f5e0 EFLAGS: 00000246
RAX: 06fe86c022bc4600 RBX: 1ffff92000705ece RCX: ffffc9000382f603
RDX: 0000000000000005 RSI: ffffffff8b0c14c0 RDI: ffffffff8b5d6dc0
RBP: ffffc9000382f720 R08: dffffc0000000000 R09: fffffbfff1d33c96
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff92000705ec8
R13: 0000000000000246 R14: ffffc9000382f670 R15: dffffc0000000000
 __raw_spin_unlock include/linux/spinlock_api_smp.h:141 [inline]
 _raw_spin_unlock+0x12/0x40 kernel/locking/spinlock.c:186
 spin_unlock include/linux/spinlock.h:391 [inline]
 __text_poke+0x81a/0x9a0 arch/x86/kernel/alternative.c:1216
 text_poke arch/x86/kernel/alternative.c:1240 [inline]
 text_poke_bp_batch+0x153/0x940 arch/x86/kernel/alternative.c:1531
 text_poke_flush arch/x86/kernel/alternative.c:1725 [inline]
 text_poke_finish+0x16/0x30 arch/x86/kernel/alternative.c:1732
 arch_jump_label_transform_apply+0x13/0x20 arch/x86/kernel/jump_label.c:146
 static_key_disable_cpuslocked+0xce/0x1b0 kernel/jump_label.c:235
 static_key_disable+0x16/0x20 kernel/jump_label.c:243
 tracepoint_remove_func kernel/tracepoint.c:417 [inline]
 tracepoint_probe_unregister+0x6e6/0x980 kernel/tracepoint.c:551
 trace_event_reg+0x216/0x250
 perf_trace_event_unreg+0xb0/0x1a0 kernel/trace/trace_event_perf.c:162
 perf_trace_destroy+0x98/0x140 kernel/trace/trace_event_perf.c:241
 _free_event+0xd0a/0x1090 kernel/events/core.c:5066
 put_event kernel/events/core.c:5160 [inline]
 perf_event_release_kernel+0x873/0x900 kernel/events/core.c:5285
 perf_release+0x37/0x40 kernel/events/core.c:5295
 __fput+0x3f6/0x8d0 fs/file_table.c:320
 task_work_run+0x246/0x300 kernel/task_work.c:203
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop+0xde/0x100 kernel/entry/common.c:177
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
 syscall_exit_to_user_mode+0x60/0x270 kernel/entry/common.c:303
 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:87
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7ff90d17def9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ff90df20038 EFLAGS: 00000246 ORIG_RAX: 000000000000012a
RAX: ffffffffffffffea RBX: 00007ff90d335f80 RCX: 00007ff90d17def9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000100
RBP: 00007ff90d1f0b76 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007ff90d335f80 R15: 00007ffdb31ab7e8
 </TASK>

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/09/16 20:59 linux-6.1.y 5f55cad62cc9 c673ca06 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in perf_release
2024/09/16 20:58 linux-6.1.y 5f55cad62cc9 c673ca06 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in perf_release
* Struck through repros no longer work on HEAD.