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INFO: rcu detected stall in perf_release (3)

Status: upstream: reported syz repro on 2026/06/17 21:48
Reported-by: syzbot+979a4989b13b8f2ee852@syzkaller.appspotmail.com
First crash: 10d, last: 14h24m
▶ ▼ Similar bugs (8)
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 2 67d 175d 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 4 19d 238d 0/3 upstream: reported syz repro on 2025/11/02 03:41
linux-6.1 INFO: rcu detected stall in perf_release 1 2 649d 649d 0/3 auto-obsoleted due to no activity on 2024/12/25 21:00
linux-6.1 INFO: rcu detected stall in perf_release (2) 1 C inconclusive 3 212d 262d 0/3 auto-obsoleted due to no activity on 2026/03/07 13:59
linux-6.6 INFO: rcu detected stall in perf_release 1 C done 1 304d 304d 2/2 fixed on 2025/10/06 10:09
upstream INFO: rcu detected stall in perf_release mm cgroups 1 19 2397d 2418d 0/29 auto-closed as invalid on 2020/03/03 09:44
android-5-15 BUG: soft lockup in perf_release (2) 1 1 455d 455d 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 736d 799d 0/2 auto-obsoleted due to no activity on 2024/09/19 17:30

Sample crash report:
rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: { 0-.... } 2686 jiffies s: 3177 root: 0x1/.
rcu: blocking rcu_node structures (internal RCU debug):
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 4570 Comm: syz.1.95 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
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:native_write_msr arch/x86/include/asm/msr.h:147 [inline]
RIP: 0010:wrmsr arch/x86/include/asm/msr.h:254 [inline]
RIP: 0010:native_apic_msr_write+0x35/0x50 arch/x86/include/asm/apic.h:206
Code: 74 2a 83 ff 30 74 25 eb 10 81 ff d0 00 00 00 74 1b 81 ff e0 00 00 00 74 13 c1 ef 04 81 c7 00 08 00 00 89 f9 89 f0 31 d2 0f 30 <66> 90 c3 89 f6 31 d2 e9 ff 50 00 03 66 2e 0f 1f 84 00 00 00 00 00
RSP: 0018:ffffc90000007248 EFLAGS: 00000046
RAX: 00000000000000f6 RBX: ffffffff8c651b88 RCX: 000000000000083f
RDX: 0000000000000000 RSI: 00000000000000f6 RDI: 000000000000083f
RBP: 0000000000000000 R08: ffffc900000071c7 R09: 1ffff92000000e38
R10: dffffc0000000000 R11: fffff52000000e39 R12: 0000000000000000
R13: dffffc0000000001 R14: dffffc0000000000 R15: 0000000000000000
FS:  0000555560cd5500(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b30963fff CR3: 000000005cf7b000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 arch_irq_work_raise+0x82/0xd0 arch/x86/kernel/irq_work.c:31
 irq_work_queue_on+0x13c/0x260 kernel/irq_work.c:165
 rcu_read_unlock_special+0x3c9/0x510 kernel/rcu/tree_plugin.h:678
 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:426
 rcu_read_unlock include/linux/rcupdate.h:823 [inline]
 __perf_event_output kernel/events/core.c:7741 [inline]
 perf_event_output_forward+0x271/0x2f0 kernel/events/core.c:7750
 __perf_event_overflow+0x457/0x630 kernel/events/core.c:9496
 perf_swevent_overflow kernel/events/core.c:9579 [inline]
 perf_swevent_event+0x315/0x570 kernel/events/core.c:9630
 perf_tp_event+0x36b/0xc10 kernel/events/core.c:10064
 perf_trace_run_bpf_submit+0xf3/0x1c0 kernel/events/core.c:10032
 perf_trace_preemptirq_template+0x268/0x320 include/trace/events/preemptirq.h:14
 trace_irq_enable_rcuidle+0xd3/0x140 include/trace/events/preemptirq.h:40
 trace_hardirqs_on+0x24/0x40 kernel/trace/trace_preemptirq.c:44
 asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:728
RIP: 0010:rcu_read_unlock_special+0x7f/0x510 kernel/rcu/tree_plugin.h:685
Code: eb 03 48 b8 f1 f1 f1 f1 f8 f2 f2 f2 4a 89 04 2b 42 c7 44 2b 08 f8 f3 f3 f3 65 44 8b 35 e2 82 95 7e 41 f7 c6 00 00 f0 00 74 40 <48> c7 44 24 40 0e 36 e0 45 4a c7 04 2b 00 00 00 00 42 c7 44 2b 08
RSP: 0018:ffffc90000007ae0 EFLAGS: 00000206
RAX: 5b7d4bbb5d364e00 RBX: 1ffff92000000f64 RCX: 5b7d4bbb5d364e00
RDX: dffffc0000000000 RSI: ffffffff8a8c17a0 RDI: ffffffff8adee1a0
RBP: ffffc90000007bd0 R08: ffffffff90af2357 R09: 1ffffffff215e46a
R10: dffffc0000000000 R11: fffffbfff215e46b R12: 0000000000000246
R13: dffffc0000000000 R14: ffff8880b8e3bb00 R15: 0000000000000001
 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:426
 rcu_read_unlock include/linux/rcupdate.h:823 [inline]
 ieee80211_iterate_active_interfaces_atomic+0x156/0x170 net/mac80211/util.c:826
 mac80211_hwsim_beacon+0xb7/0x1b0 drivers/net/wireless/mac80211_hwsim.c:2147
 __run_hrtimer kernel/time/hrtimer.c:1751 [inline]
 __hrtimer_run_queues+0x522/0xc90 kernel/time/hrtimer.c:1815
 hrtimer_run_softirq+0x173/0x290 kernel/time/hrtimer.c:1832
 handle_softirqs+0x291/0x910 kernel/softirq.c:596
 __do_softirq kernel/softirq.c:630 [inline]
 invoke_softirq kernel/softirq.c:470 [inline]
 __irq_exit_rcu+0x13b/0x230 kernel/softirq.c:679
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:691
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
 sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1118
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:_test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline]
RIP: 0010:cpumask_test_cpu include/linux/cpumask.h:444 [inline]
RIP: 0010:cpu_online include/linux/cpumask.h:1030 [inline]
RIP: 0010:trace_contention_end+0x3e/0x170 include/trace/events/lock.h:122
Code: 90 65 8b 1d c4 c9 9e 7e 48 c7 c0 70 11 20 8e 48 c1 e8 03 42 0f b6 04 20 84 c0 75 45 3b 1d 7a c1 bc 0c 73 35 41 89 de c1 eb 06 <48> 8d 3c dd 68 0f 20 8e be 08 00 00 00 e8 50 fa 6f 00 4c 0f a3 35
RSP: 0018:ffffc90003937ab0 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 5b7d4bbb5d364e00
RDX: 0000000000000001 RSI: 0000000000000000 RDI: ffff88802f5eee38
RBP: ffffc90003937c40 R08: ffffc90003937a67 R09: 1ffff92000726f4c
R10: dffffc0000000000 R11: fffff52000726f4d R12: dffffc0000000000
R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000000
 __mutex_lock_common kernel/locking/mutex.c:612 [inline]
 __mutex_lock+0x1a1/0xae0 kernel/locking/mutex.c:747
 perf_remove_from_owner+0x244/0x4c0 kernel/events/core.c:5140
 perf_event_release_kernel+0x127/0x850 kernel/events/core.c:5187
 perf_release+0x37/0x40 kernel/events/core.c:5297
 __fput+0x20a/0x8b0 fs/file_table.c:320
 task_work_run+0x1d0/0x260 kernel/task_work.c:203
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
 syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f71ab59ce59
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffe7ead1d88 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 00007ffe7ead1e70 RCX: 00007f71ab59ce59
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 0000000000030776 R08: 0000000000000001 R09: 0000000000000000
R10: 0000001b2fd20000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f71ab815fac R14: 00007f71ab815fa8 R15: 00007f71ab815fa0
 </TASK>

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/06/27 16:56 linux-6.1.y fdb6fcb41cc7 fb92f11c .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in perf_release
2026/06/17 21:47 linux-6.1.y 228da13e907e b62b3ded .config console log report syz / log [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.