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INFO: rcu detected stall in perf_event_open (2)

Status: upstream: reported C repro on 2025/11/10 01:14
Bug presence: origin:lts-only
[Documentation on labels]
Reported-by: syzbot+87408f570c7f21d4f57d@syzkaller.appspotmail.com
First crash: 146d, last: 1d00h
▶ ▼ Bug presence (2)
Date Name Commit Repro Result
2025/11/14 linux-6.6.y (ToT) 0a805b6ea8cd C [report] INFO: rcu detected stall in perf_event_open
2025/11/14 upstream (ToT) d4f8cccc6230 C Didn't crash
▶ ▼ Similar bugs (17)
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 77 6h22m 817d 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 1651d 1651d 0/29 auto-closed as invalid on 2021/11/26 20:49
upstream INFO: rcu detected stall in perf_event_open kernel 1 1 1747d 1747d 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 C done 50 9d04h 559d 0/3 upstream: reported C repro on 2024/09/23 05:55
linux-6.6 INFO: rcu detected stall in perf_event_open 1 C done 4 220d 234d 2/2 fixed on 2025/10/06 10:09
upstream BUG: soft lockup in perf_event_open (2) net 1 8 22d 28d 0/29 upstream: reported on 2026/03/08 04:57
upstream BUG: soft lockup in perf_event_open trace bpf 1 2 284d 280d 0/29 auto-obsoleted due to no activity on 2025/09/23 09:29
upstream INFO: rcu detected stall in __se_sys_perf_event_open perf 1 1 2101d 2101d 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 2279d 2279d 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 2279d 2279d 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 2314d 2315d 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 663d 663d 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 1082d 1082d 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 2759d 2757d 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 699d 699d 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 674d 670d 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 442d 549d 0/29 auto-obsoleted due to no activity on 2025/04/18 04:31
▶ ▼ Fix bisection attempts (1)
Created Duration User Patch Repo Result
2026/01/15 04:44 2h33m fix candidate upstream OK (0) job log

Sample crash report:
rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	1-....: (10500 ticks this GP) idle=7904/1/0x4000000000000000 softirq=12784/12784 fqs=4374
rcu: 	         hardirqs   softirqs   csw/system
rcu: 	 number:  1343325          0            0
rcu: 	cputime:    19269      33220           70   ==> 52490(ms)
rcu: 	(t=10500 jiffies g=11909 q=655 ncpus=2)
CPU: 1 PID: 5931 Comm: syz.2.19 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:seqcount_lockdep_reader_access+0x19a/0x1d0 include/linux/seqlock.h:105
Code: 00 4d 85 e4 75 16 e8 b5 c4 0f 00 eb 15 e8 ae c4 0f 00 e8 89 bc 0d 09 4d 85 e4 74 ea e8 9f c4 0f 00 fb 48 c7 04 24 0e 36 e0 45 <4b> c7 04 3e 00 00 00 00 43 c7 44 3e 08 00 00 00 00 65 48 8b 04 25
RSP: 0018:ffffc900001efb00 EFLAGS: 00000246
RAX: ffffffff817757c1 RBX: 0000000000000000 RCX: ffff888024311e00
RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc900001efbb8 R08: ffffffff911c15ef R09: 1ffffffff22382bd
R10: dffffc0000000000 R11: fffffbfff22382be R12: 0000000000000200
R13: 000001fb63109b96 R14: 1ffff9200003df60 R15: dffffc0000000000
FS:  000055557e670500(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b34863fff CR3: 00000000769ec000 CR4: 00000000003506e0
Call Trace:
 <IRQ>
 ktime_get_with_offset+0x94/0x330 kernel/time/timekeeping.c:889
 ktime_get_real include/linux/timekeeping.h:79 [inline]
 mac80211_hwsim_get_tsf_raw drivers/net/wireless/virtual/mac80211_hwsim.c:1180 [inline]
 mac80211_hwsim_tx_frame_no_nl+0x709/0x11a0 drivers/net/wireless/virtual/mac80211_hwsim.c:1787
 mac80211_hwsim_tx+0x1808/0x2720 drivers/net/wireless/virtual/mac80211_hwsim.c:2058
 drv_tx net/mac80211/driver-ops.h:37 [inline]
 wake_tx_push_queue net/mac80211/util.c:305 [inline]
 ieee80211_handle_wake_tx_queue+0x199/0x2b0 net/mac80211/util.c:322
 drv_wake_tx_queue net/mac80211/driver-ops.h:1251 [inline]
 schedule_and_wake_txq net/mac80211/driver-ops.h:1258 [inline]
 ieee80211_queue_skb+0x1a3e/0x21c0 net/mac80211/tx.c:1678
 ieee80211_tx+0x2c3/0x460 net/mac80211/tx.c:1980
 __ieee80211_subif_start_xmit+0xe10/0x1500 net/mac80211/tx.c:4333
 ieee80211_subif_start_xmit+0xf4/0x560 net/mac80211/tx.c:4527
 __netdev_start_xmit include/linux/netdevice.h:4943 [inline]
 netdev_start_xmit include/linux/netdevice.h:4957 [inline]
 xmit_one net/core/dev.c:3632 [inline]
 dev_hard_start_xmit+0x246/0x740 net/core/dev.c:3648
 __dev_queue_xmit+0x19a3/0x3660 net/core/dev.c:4442
 neigh_output include/net/neighbour.h:543 [inline]
 ip6_finish_output2+0xe3d/0x1630 net/ipv6/ip6_output.c:141
 dst_output include/net/dst.h:467 [inline]
 NF_HOOK include/linux/netfilter.h:304 [inline]
 ndisc_send_skb+0xc26/0x14f0 net/ipv6/ndisc.c:513
 addrconf_rs_timer+0x2d5/0x630 net/ipv6/addrconf.c:4024
 call_timer_fn+0x189/0x540 kernel/time/timer.c:1701
 expire_timers kernel/time/timer.c:1752 [inline]
 __run_timers+0x542/0x800 kernel/time/timer.c:2023
 run_timer_softirq+0x67/0xf0 kernel/time/timer.c:2036
 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+0xd3/0x190 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:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0xc0/0x120 kernel/locking/spinlock.c:194
Code: c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f7 44 24 20 00 02 00 00 41 c6 04 07 f8 75 4b f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 <e8> 0b c9 cd f6 65 8b 05 2c f8 74 75 85 c0 74 3c 48 c7 04 24 0e 36
RSP: 0018:ffffc9000367fca0 EFLAGS: 00000206
RAX: dffffc0000000004 RBX: 0000000000000a06 RCX: 984e95a45ff81e00
RDX: dffffc0000000000 RSI: ffffffff8acac960 RDI: 0000000000000001
RBP: ffffc9000367fd30 R08: ffffffff911c160f R09: 1ffffffff22382c1
R10: dffffc0000000000 R11: fffffbfff22382c2 R12: dffffc0000000000
R13: 1ffff920006cffb8 R14: ffff888075514400 R15: 1ffff920006cff94
 __do_sys_perf_event_open kernel/events/core.c:12916 [inline]
 __se_sys_perf_event_open+0x183e/0x1c50 kernel/events/core.c:12567
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7feac519c799
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:00007ffe93dbc1f8 EFLAGS: 00000246 ORIG_RAX: 000000000000012a
RAX: ffffffffffffffda RBX: 00007feac5415fa0 RCX: 00007feac519c799
RDX: ffffffffffffffff RSI: 0000000000000000 RDI: 0000200000000140
RBP: 00007feac5232c99 R08: 0000000000000002 R09: 0000000000000000
R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000
R13: 00007feac5415fac R14: 00007feac5415fa0 R15: 00007feac5415fa0
 </TASK>

Crashes (48):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/03/22 07:55 linux-6.6.y 4fc00fe35d46 5b92003d .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in perf_event_open
2025/12/12 15:29 linux-6.6.y 5fa4793a2d2d d6526ea3 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in perf_event_open
2025/11/11 19:51 linux-6.6.y 0a805b6ea8cd 4e1406b4 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in perf_event_open
2026/04/04 22:02 linux-6.6.y 08667c1437c0 4440e7c2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in perf_event_open
2026/04/04 16:39 linux-6.6.y 08667c1437c0 4440e7c2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in perf_event_open
2026/04/03 21:29 linux-6.6.y 08667c1437c0 4440e7c2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in perf_event_open
2026/03/22 23:31 linux-6.6.y 4fc00fe35d46 5b92003d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in perf_event_open
2026/03/22 01:43 linux-6.6.y 4fc00fe35d46 5b92003d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in perf_event_open
2026/03/10 23:46 linux-6.6.y 4fc00fe35d46 4683d576 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in perf_event_open
2026/03/08 08:09 linux-6.6.y 4fc00fe35d46 5cb44a80 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in perf_event_open
2026/03/07 22:14 linux-6.6.y 4fc00fe35d46 5cb44a80 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in perf_event_open
2026/03/07 18:17 linux-6.6.y 4fc00fe35d46 5cb44a80 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in perf_event_open
2026/02/21 23:45 linux-6.6.y 7a137e9bfa0e 6e7b5511 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in perf_event_open
2026/02/16 23:52 linux-6.6.y ae462074fde3 5d52cba5 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in perf_event_open
2026/02/16 06:00 linux-6.6.y 1b4ef5214f17 1e62d198 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in perf_event_open
2026/02/15 16:01 linux-6.6.y 1b4ef5214f17 1e62d198 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in perf_event_open
2026/02/14 22:36 linux-6.6.y 1b4ef5214f17 1e62d198 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in perf_event_open
2026/02/13 16:59 linux-6.6.y 1b4ef5214f17 6a673c50 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in perf_event_open
2026/02/11 10:34 linux-6.6.y c56aaf1a85ae 441e25b7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in perf_event_open
2026/02/04 10:21 linux-6.6.y 2cf6f68313dc 42b01fab .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in perf_event_open
2026/01/30 17:58 linux-6.6.y 2cf6f68313dc ae7dc18c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in perf_event_open
2026/01/26 14:49 linux-6.6.y cbb31f77b879 a4c52dd6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in perf_event_open
2026/01/24 06:25 linux-6.6.y cbb31f77b879 4f25b9b4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in perf_event_open
2026/01/23 05:20 linux-6.6.y cbb31f77b879 82c9c083 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in perf_event_open
2026/01/19 02:02 linux-6.6.y cbb31f77b879 20d37d28 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in perf_event_open
2026/01/13 00:13 linux-6.6.y c596736dadab d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in perf_event_open
2026/01/10 09:11 linux-6.6.y 5fa4793a2d2d d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in perf_event_open
2026/01/10 00:48 linux-6.6.y 5fa4793a2d2d d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in perf_event_open
2026/01/09 11:24 linux-6.6.y 5fa4793a2d2d d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in perf_event_open
2026/01/06 16:26 linux-6.6.y 5fa4793a2d2d d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in perf_event_open
2026/01/06 05:25 linux-6.6.y 5fa4793a2d2d d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in perf_event_open
2026/01/03 09:33 linux-6.6.y 5fa4793a2d2d d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in perf_event_open
2026/01/01 07:12 linux-6.6.y 5fa4793a2d2d d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in perf_event_open
2026/01/01 02:38 linux-6.6.y 5fa4793a2d2d d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in perf_event_open
2025/12/27 10:00 linux-6.6.y 5fa4793a2d2d d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in perf_event_open
2025/12/24 19:31 linux-6.6.y 5fa4793a2d2d d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in perf_event_open
2025/12/23 06:06 linux-6.6.y 5fa4793a2d2d d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in perf_event_open
2025/12/19 17:44 linux-6.6.y 5fa4793a2d2d d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in perf_event_open
2025/12/16 18:50 linux-6.6.y 5fa4793a2d2d d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in perf_event_open
2025/12/15 22:58 linux-6.6.y 5fa4793a2d2d d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in perf_event_open
2025/12/13 21:11 linux-6.6.y 5fa4793a2d2d d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in perf_event_open
2025/12/13 07:15 linux-6.6.y 5fa4793a2d2d d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in perf_event_open
2025/12/12 21:42 linux-6.6.y 5fa4793a2d2d d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in perf_event_open
2025/12/11 03:07 linux-6.6.y 5fa4793a2d2d d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in perf_event_open
2025/12/05 06:01 linux-6.6.y 4791134e4aeb d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in perf_event_open
2025/12/05 00:42 linux-6.6.y 4791134e4aeb d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in perf_event_open
2025/11/11 15:21 linux-6.6.y 0a805b6ea8cd 4e1406b4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in perf_event_open
2025/11/10 01:14 linux-6.6.y 0a805b6ea8cd 4e1406b4 .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.