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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: 197d, last: 11h19m
▶ ▼ 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 92 13h37m 867d 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 1701d 1701d 0/29 auto-closed as invalid on 2021/11/26 20:49
upstream INFO: rcu detected stall in perf_event_open kernel 1 1 1798d 1798d 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 63 7h01m 610d 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 271d 284d 2/2 fixed on 2025/10/06 10:09
upstream BUG: soft lockup in perf_event_open (2) net 1 8 73d 79d 0/29 upstream: reported on 2026/03/08 04:57
upstream BUG: soft lockup in perf_event_open trace bpf 1 2 334d 331d 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 2152d 2152d 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 2330d 2330d 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 2329d 2329d 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 2364d 2366d 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 714d 714d 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 1133d 1133d 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 2809d 2807d 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 750d 750d 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 725d 721d 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 493d 600d 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: 	0-....: (10501 ticks this GP) idle=c404/1/0x4000000000000000 softirq=14197/14197 fqs=2152
rcu: 	         hardirqs   softirqs   csw/system
rcu: 	 number:   894090          0            0
rcu: 	cputime:    11267      22666           45   ==> 33950(ms)
rcu: 	(t=10502 jiffies g=12885 q=1829 ncpus=2)
CPU: 0 PID: 5980 Comm: syz.1.18 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:check_canary+0x93/0x980 mm/kfence/core.c:362
Code: ad 48 25 f8 0f 00 00 4c 89 64 24 10 74 5e 4c 29 e5 48 83 c5 f8 4c 89 e0 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df 80 3c 08 00 <74> 08 4c 89 e7 e8 13 a2 ff ff 4d 8b 2c 24 48 89 df 4c 89 ee e8 f4
RSP: 0018:ffffc90000007328 EFLAGS: 00000246
RAX: 1ffff110477b0428 RBX: adacafaea9a8abaa RCX: dffffc0000000000
RDX: 0000000000000100 RSI: adacafaea9a8abaa RDI: adacafaea9a8abaa
RBP: 0000000000000bf8 R08: ffffffff9733687f R09: 1ffffffff2e66d0f
R10: dffffc0000000000 R11: fffffbfff2e66d10 R12: ffff88823bd82140
R13: adacafaea9a8abaa R14: 1ffff11047ff92cd R15: ffff88823ffc9600
FS:  000055556b29b500(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000000000139b CR3: 000000007724e000 CR4: 00000000003506f0
Call Trace:
 <IRQ>
 kfence_guarded_free+0x258/0x4b0 mm/kfence/core.c:536
 skb_kfree_head net/core/skbuff.c:946 [inline]
 skb_free_head net/core/skbuff.c:958 [inline]
 skb_release_data+0x5dc/0x7b0 net/core/skbuff.c:988
 skb_release_all net/core/skbuff.c:1054 [inline]
 __kfree_skb net/core/skbuff.c:1068 [inline]
 consume_skb+0xb2/0x110 net/core/skbuff.c:1284
 nsim_start_xmit+0x9e/0xc0 drivers/net/netdevsim/netdev.c:42
 __netdev_start_xmit include/linux/netdevice.h:4943 [inline]
 netdev_start_xmit include/linux/netdevice.h:4957 [inline]
 xmit_one net/core/dev.c:3644 [inline]
 dev_hard_start_xmit+0x246/0x740 net/core/dev.c:3660
 __dev_queue_xmit+0x19a3/0x3660 net/core/dev.c:4454
 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:rcu_read_lock_sched include/linux/rcupdate.h:876 [inline]
RIP: 0010:fd_install+0x4f/0x4e0 fs/file.c:595
Code: cd 90 ff 65 4c 8b 35 10 57 0d 7e 49 81 c6 f8 08 00 00 4c 89 f0 48 c1 e8 03 80 3c 18 00 74 08 4c 89 f7 e8 74 0c e9 ff 4d 8b 3e <bf> 01 00 00 00 e8 b7 2d 66 ff 4c 8d 35 00 00 00 00 48 c7 c7 e0 21
RSP: 0018:ffffc90003447cf8 EFLAGS: 00000246
RAX: 1ffff1100fc6489f RBX: dffffc0000000000 RCX: ffff88807e323c00
RDX: 0000000000000000 RSI: ffff888024ff3180 RDI: 0000000000000004
RBP: ffffc90003447f10 R08: ffffc90003447cc7 R09: 1ffff92000688f98
R10: dffffc0000000000 R11: fffff52000688f99 R12: ffff88801c270918
R13: 0000000000000004 R14: ffff88807e3244f8 R15: ffff88802d567840
 __do_sys_perf_event_open kernel/events/core.c:12978 [inline]
 __se_sys_perf_event_open+0x19f3/0x1c50 kernel/events/core.c:12609
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fdc8d19ce59
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:00007fff4a142bc8 EFLAGS: 00000246 ORIG_RAX: 000000000000012a
RAX: ffffffffffffffda RBX: 00007fdc8d415fa0 RCX: 00007fdc8d19ce59
RDX: ffffff7fffffffff RSI: 0000000000000000 RDI: 0000200000000480
RBP: 00007fdc8d232d6f R08: 0000000000000008 R09: 0000000000000000
R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000
R13: 00007fdc8d415fac R14: 00007fdc8d415fa0 R15: 00007fdc8d415fa0
 </TASK>

Crashes (56):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/05/25 19:59 linux-6.6.y 0a40c6fbd105 c69befb3 .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
2026/03/22 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
2026/05/25 15:11 linux-6.6.y 0a40c6fbd105 c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in perf_event_open
2026/05/20 22:58 linux-6.6.y eac8889a3a1c 62fb93a2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in perf_event_open
2026/05/17 05:19 linux-6.6.y 4d922539ad7d de5aae85 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in perf_event_open
2026/05/15 07:21 linux-6.6.y 3b9f64db0496 6ccb967e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in perf_event_open
2026/05/11 04:53 linux-6.6.y 3b9f64db0496 29233ece .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in perf_event_open
2026/05/09 21:01 linux-6.6.y 3b9f64db0496 29233ece .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in perf_event_open
2026/05/04 06:52 linux-6.6.y 258cf62a6dfd a0d91488 .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 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.