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INFO: rcu detected stall in perf_event_open

Status: upstream: reported on 2025/08/14 11:08
Reported-by: syzbot+0c40b0eae227145b6069@syzkaller.appspotmail.com
First crash: 13d, last: 1d21h
▶ ▼ Similar bugs (15)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 INFO: rcu detected stall in sys_perf_event_open (2) origin:lts-only 1 C error 14 2d01h 596d 0/3 upstream: reported C repro on 2024/01/09 18:19
upstream INFO: rcu detected stall in perf_event_open (2) perf 1 1 1430d 1430d 0/29 auto-closed as invalid on 2021/11/26 20:49
upstream INFO: rcu detected stall in perf_event_open kernel 1 1 1527d 1527d 0/29 auto-closed as invalid on 2021/09/21 01:14
linux-6.1 INFO: rcu detected stall in sys_perf_event_open (2) origin:lts-only 1 syz done 8 11d 338d 0/3 upstream: reported syz repro on 2024/09/23 05:55
upstream BUG: soft lockup in perf_event_open bpf trace 1 2 63d 59d 0/29 moderation: reported on 2025/06/29 04:38
upstream INFO: rcu detected stall in __se_sys_perf_event_open perf 1 1 1881d 1881d 0/29 auto-closed as invalid on 2020/10/02 02:08
upstream INFO: rcu detected stall in sys_perf_event_open (3) perf 1 1 2059d 2059d 0/29 closed as invalid on 2020/01/08 05:23
upstream INFO: rcu detected stall in sys_perf_event_open (4) perf 1 1 2058d 2058d 0/29 closed as invalid on 2020/01/09 08:13
upstream INFO: rcu detected stall in sys_perf_event_open (2) perf 1 8 2093d 2095d 0/29 closed as invalid on 2019/12/04 14:14
linux-6.1 INFO: rcu detected stall in sys_perf_event_open 1 1 443d 443d 0/3 auto-obsoleted due to no activity on 2024/09/19 01:45
linux-5.15 INFO: rcu detected stall in sys_perf_event_open 1 1 861d 861d 0/3 auto-obsoleted due to no activity on 2023/08/17 04:33
upstream INFO: rcu detected stall in sys_perf_event_open perf 1 1 2538d 2536d 0/29 auto-closed as invalid on 2019/03/14 17:19
android-5-15 BUG: soft lockup in sys_perf_event_open 1 1 478d 478d 0/2 auto-obsoleted due to no activity on 2024/08/04 07:07
upstream BUG: soft lockup in sys_perf_event_open perf 1 1 454d 450d 0/29 auto-obsoleted due to no activity on 2024/08/29 01:52
upstream BUG: soft lockup in sys_perf_event_open (2) kvm fs 1 6 221d 329d 0/29 auto-obsoleted due to no activity on 2025/04/18 04:31

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-....: (1 GPs behind) idle=0f8c/1/0x4000000000000000 softirq=21934/21935 fqs=5250
rcu: 	         hardirqs   softirqs   csw/system
rcu: 	 number: 11083438          0            0
rcu: 	cputime:     6217      46300            0   ==> 52500(ms)
rcu: 	(detected by 1, t=10502 jiffies, g=22281, q=349 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 6706 Comm: syz.0.277 Not tainted 6.6.102-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
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+0x39/0x50 arch/x86/include/asm/apic.h:196
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 f3 0f 1e fa 89 f6 31 d2 e9 47 61 18 03 0f 1f 80 00 00 00
RSP: 0018:ffffc90000007290 EFLAGS: 00000046
RAX: 00000000000000f6 RBX: 0000000000000200 RCX: 000000000000083f
RDX: 0000000000000000 RSI: 00000000000000f6 RDI: 000000000000083f
RBP: 0000000000000000 R08: ffffc900000071e7 R09: 1ffff92000000e3c
R10: dffffc0000000000 R11: fffff52000000e3d R12: 0000000000000000
R13: dffffc0000000001 R14: 0000000000000000 R15: 0000000000000000
FS:  00007f6d2776e6c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c285275 CR3: 0000000079196000 CR4: 00000000003506f0
DR0: 0000200000000300 DR1: 0000200000000300 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 __apic_send_IPI_self arch/x86/include/asm/apic.h:454 [inline]
 arch_irq_work_raise+0x68/0x70 arch/x86/kernel/irq_work.c:31
 irq_work_queue_on+0x122/0x220 kernel/irq_work.c:175
 rcu_read_unlock_special+0x3a7/0x4c0 kernel/rcu/tree_plugin.h:675
 __rcu_read_unlock+0x7c/0xd0 kernel/rcu/tree_plugin.h:426
 rcu_read_unlock include/linux/rcupdate.h:818 [inline]
 __perf_event_output kernel/events/core.c:7983 [inline]
 perf_event_output_forward+0x2e6/0x3a0 kernel/events/core.c:7992
 __perf_event_overflow+0x447/0x630 kernel/events/core.c:9717
 perf_swevent_overflow kernel/events/core.c:9793 [inline]
 perf_swevent_event+0x2f5/0x5c0 kernel/events/core.c:-1
 perf_tp_event+0x4f9/0x13a0 kernel/events/core.c:10343
 perf_trace_run_bpf_submit+0xf4/0x1c0 kernel/events/core.c:10267
 perf_trace_preemptirq_template+0x281/0x340 include/trace/events/preemptirq.h:14
 trace_irq_enable+0xbf/0xe0 include/trace/events/preemptirq.h:40
 trace_hardirqs_on+0x18/0x40 kernel/trace/trace_preemptirq.c:56
 asm_sysvec_irq_work+0x1a/0x20 arch/x86/include/asm/idtentry.h:723
RIP: 0010:rcu_read_unlock_special+0x88/0x4c0 kernel/rcu/tree_plugin.h:682
Code: f1 f1 f1 00 f2 f2 f2 4a 89 04 2b 66 42 c7 44 2b 09 f3 f3 42 c6 44 2b 0b f3 65 44 8b 35 39 58 93 7e 41 f7 c6 00 00 f0 00 74 45 <48> c7 44 24 40 0e 36 e0 45 4a c7 04 2b 00 00 00 00 66 42 c7 44 2b
RSP: 0018:ffffc90000007b00 EFLAGS: 00000206
RAX: 8130c3a384c34900 RBX: 1ffff92000000f68 RCX: 8130c3a384c34900
RDX: dffffc0000000000 RSI: ffffffff8aaab9c0 RDI: ffffffff8afc66c0
RBP: ffffc90000007bf0 R08: ffffffff90da35ff R09: 1ffffffff21b46bf
R10: dffffc0000000000 R11: fffffbfff21b46c0 R12: ffffffff8cd35400
R13: dffffc0000000000 R14: 0000000000000246 R15: 0000000000000001
 __rcu_read_unlock+0x7c/0xd0 kernel/rcu/tree_plugin.h:426
 rcu_read_unlock include/linux/rcupdate.h:818 [inline]
 ieee80211_iterate_active_interfaces_atomic+0x15a/0x180 net/mac80211/util.c:804
 mac80211_hwsim_beacon+0xbb/0x1b0 drivers/net/wireless/virtual/mac80211_hwsim.c:2295
 __run_hrtimer kernel/time/hrtimer.c:1755 [inline]
 __hrtimer_run_queues+0x51e/0xc40 kernel/time/hrtimer.c:1819
 hrtimer_run_softirq+0x187/0x2b0 kernel/time/hrtimer.c:1836
 handle_softirqs+0x280/0x820 kernel/softirq.c:578
 __do_softirq kernel/softirq.c:612 [inline]
 invoke_softirq kernel/softirq.c:452 [inline]
 __irq_exit_rcu+0xc7/0x190 kernel/softirq.c:661
 irq_exit_rcu+0x9/0x20 kernel/softirq.c:673
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline]
 sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1088
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:preempt_schedule_irq+0xb0/0x140 kernel/sched/core.c:7009
Code: 44 24 20 f6 44 24 21 02 74 0b 0f 0b 48 f7 03 08 00 00 00 74 63 bf 01 00 00 00 e8 4b da e5 f6 e8 46 5f 16 f7 fb bf 01 00 00 00 <e8> db b5 ff ff 48 c7 44 24 40 00 00 00 00 9c 8f 44 24 40 8b 44 24
RSP: 0018:ffffc9000bb17a80 EFLAGS: 00000282
RAX: 8130c3a384c34900 RBX: 0000000000000000 RCX: 8130c3a384c34900
RDX: dffffc0000000000 RSI: ffffffff8aaab9c0 RDI: 0000000000000001
RBP: ffffc9000bb17b20 R08: ffffffff90da35ff R09: 1ffffffff21b46bf
R10: dffffc0000000000 R11: fffffbfff21b46c0 R12: 0000000000000000
R13: 0000000000000000 R14: dffffc0000000000 R15: 1ffff92001762f50
 irqentry_exit+0x67/0x70 kernel/entry/common.c:438
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:perf_install_in_context+0x6fb/0x8e0 kernel/events/core.c:2972
Code: d8 ff 48 8b 7c 24 10 48 8b 5c 24 18 48 89 de e8 eb df 01 00 48 89 df e8 73 81 c9 08 48 8b 5c 24 20 48 c7 44 24 60 0e 36 e0 45 <42> c7 04 23 00 00 00 00 42 c7 44 23 08 00 00 00 00 42 c7 44 23 10
RSP: 0018:ffffc9000bb17be0 EFLAGS: 00000283
RAX: ffffffff81ad6f09 RBX: 1ffff92001762f88 RCX: 0000000000080000
RDX: ffffc9000c5d9000 RSI: 0000000000001831 RDI: 0000000000001832
RBP: ffffc9000bb17d30 R08: ffffffff90da35ff R09: 1ffffffff21b46bf
R10: dffffc0000000000 R11: fffffbfff21b46c0 R12: dffffc0000000000
R13: ffff888021013c14 R14: ffffc9000bb17c60 R15: dffffc0000000000
 __do_sys_perf_event_open kernel/events/core.c:12914 [inline]
 __se_sys_perf_event_open+0x17fa/0x1c20 kernel/events/core.c:12566
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f6d2698ebe9
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:00007f6d2776e038 EFLAGS: 00000246 ORIG_RAX: 000000000000012a
RAX: ffffffffffffffda RBX: 00007f6d26bb5fa0 RCX: 00007f6d2698ebe9
RDX: ffefffffffffffff RSI: 0000000000000000 RDI: 0000200000000700
RBP: 00007f6d26a11e19 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000
R13: 00007f6d26bb6038 R14: 00007f6d26bb5fa0 R15: 00007ffd9da23f78
 </TASK>

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/08/26 05:33 linux-6.6.y bb9c90ab9c5a bf27483f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in perf_event_open
2025/08/14 11:07 linux-6.6.y 3a8ababb8b6a 22ec1469 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in perf_event_open
* Struck through repros no longer work on HEAD.