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INFO: rcu detected stall in cleanup_net

Status: upstream: reported C repro on 2023/07/11 05:04
Bug presence: origin:lts-only
[Documentation on labels]
Reported-by: syzbot+f5d4d279dfe9b422732e@syzkaller.appspotmail.com
First crash: 827d, last: 4d21h
▶ ▼ Bug presence (2)
Date Name Commit Repro Result
2025/09/05 linux-5.15.y (ToT) 7a6c2d093c45 C [report] INFO: rcu detected stall in sys_rt_sigreturn
2025/09/05 upstream (ToT) d69eb204c255 C Didn't crash
▶ ▼ Similar bugs (15)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in cleanup_net (3) net 1 1 2222d 2222d 0/29 auto-closed as invalid on 2019/12/15 02:54
upstream INFO: rcu detected stall in cleanup_net (6) net 1 63 769d 1012d 0/29 closed as invalid on 2023/10/27 14:39
linux-4.19 INFO: rcu detected stall in cleanup_net (2) 1 4 1572d 1703d 0/1 auto-closed as invalid on 2021/10/25 03:43
upstream INFO: rcu detected stall in cleanup_net kernel 1 5 2653d 2721d 0/29 closed as invalid on 2018/09/05 12:51
upstream INFO: rcu detected stall in cleanup_net (4) kernel 1 C done 5 1866d 1862d 15/29 fixed on 2020/10/10 01:52
upstream INFO: rcu detected stall in cleanup_net (5) net 1 24 1350d 1610d 0/29 closed as invalid on 2022/02/08 10:00
linux-4.19 INFO: rcu detected stall in cleanup_net 1 1 2094d 2094d 0/1 auto-closed as invalid on 2020/05/21 02:17
linux-6.1 INFO: rcu detected stall in cleanup_net origin:lts-only 1 syz inconclusive 141 12d 826d 0/3 upstream: reported syz repro on 2023/07/12 14:45
upstream INFO: rcu detected stall in cleanup_net (2) kernel 1 1 2565d 2561d 0/29 auto-closed as invalid on 2019/04/05 22:14
upstream INFO: rcu detected stall in cleanup_net (7) kernfs rdma bridge 1 15 322d 699d 0/29 auto-obsoleted due to no activity on 2025/02/25 20:50
android-5-10 BUG: soft lockup in cleanup_net 1 1 160d 160d 0/2 auto-obsoleted due to no activity on 2025/08/06 14:41
linux-4.19 BUG: soft lockup in cleanup_net (2) 1 C 3 955d 1067d 0/1 upstream: reported C repro on 2022/11/13 07:04
android-5-15 BUG: soft lockup in cleanup_net origin:lts 1 syz 6 401d 528d 0/2 auto-obsoleted due to no activity on 2024/12/08 05:58
android-6-1 BUG: soft lockup in cleanup_net 1 1 271d 271d 0/2 auto-obsoleted due to no activity on 2025/04/17 10:35
linux-4.19 BUG: soft lockup in cleanup_net 1 4 1201d 1414d 0/1 auto-obsoleted due to no activity on 2022/10/30 18:15
▶ ▼ Last patch testing requests (1)
Created Duration User Patch Repo Result
2025/01/26 11:49 14m retest repro linux-5.15.y report log
▶ ▼ Fix bisection attempts (3)
Created Duration User Patch Repo Result
2025/05/02 16:05 1h28m fix candidate upstream error job log
2025/02/08 14:00 1m fix candidate upstream error job log
2024/12/14 03:11 7m fix candidate upstream error job log

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...0: (1 GPs behind) idle=ea5/1/0x4000000000000000 softirq=7088/7089 fqs=2100 
	(detected by 0, t=10506 jiffies, g=8313, q=437)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 154 Comm: kworker/u4:2 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Workqueue: netns cleanup_net
RIP: 0010:cpu_max_bits_warn include/linux/cpumask.h:108 [inline]
RIP: 0010:cpumask_check include/linux/cpumask.h:115 [inline]
RIP: 0010:cpumask_test_cpu include/linux/cpumask.h:344 [inline]
RIP: 0010:cpu_online include/linux/cpumask.h:895 [inline]
RIP: 0010:trace_hrtimer_expire_exit include/trace/events/timer.h:283 [inline]
RIP: 0010:__run_hrtimer kernel/time/hrtimer.c:1693 [inline]
RIP: 0010:__hrtimer_run_queues+0x56a/0xc40 kernel/time/hrtimer.c:1754
Code: 43 0f b6 04 2f 84 c0 0f 85 26 03 00 00 c7 03 00 00 00 00 4c 8b 6c 24 20 0f 1f 44 00 00 e8 ce 11 10 00 65 44 8b 3d fe 5b 9a 7e <bf> 07 00 00 00 44 89 fe e8 19 15 10 00 41 83 ff 07 0f 87 ac 01 00
RSP: 0018:ffffc90000dd0d20 EFLAGS: 00000006
RAX: ffffffff8167b952 RBX: ffff88801bb10ad8 RCX: ffff88801bb10000
RDX: 0000000000010000 RSI: ffffffff8a0b2ac0 RDI: ffffffff8a59a480
RBP: ffffc90000dd0e98 R08: dffffc0000000000 R09: fffffbfff1ad323e
R10: fffffbfff1ad323e R11: 1ffffffff1ad323d R12: ffff8880b912a350
R13: 1ffff1101722546a R14: 0000000000000001 R15: 0000000000000001
FS:  0000000000000000(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000000600 CR3: 000000000be8e000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 hrtimer_interrupt+0x3bb/0x8d0 kernel/time/hrtimer.c:1816
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline]
 __sysvec_apic_timer_interrupt+0x137/0x4a0 arch/x86/kernel/apic/apic.c:1114
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
 sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1108
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:lockdep_unregister_key+0x4ae/0x500 kernel/locking/lockdep.c:6334
Code: 48 3b 84 24 80 00 00 00 75 39 48 8d 65 d8 5b 41 5c 41 5d 41 5e 41 5f 5d c3 e8 0e 50 4c 08 41 f7 c4 00 02 00 00 74 8b fb 84 db <75> 8a eb 9b 0f 0b e9 58 ff ff ff 0f 0b e9 c4 fe ff ff 0f 0b e9 11
RSP: 0018:ffffc900020077a0 EFLAGS: 00000202
RAX: 7ce4b6df42a0b000 RBX: ffff88807d756901 RCX: 7ce4b6df42a0b000
RDX: 0000000000000001 RSI: ffffffff8a0b2620 RDI: ffffffff8a59a480
RBP: ffffc90002007880 R08: dffffc0000000000 R09: fffffbfff1fed941
R10: fffffbfff1fed941 R11: 1ffffffff1fed940 R12: 0000000000000a06
R13: ffff88807d756929 R14: ffffffff8ff6c018 R15: 1ffff92000400ef8
 wq_unregister_lockdep kernel/workqueue.c:3518 [inline]
 destroy_workqueue+0x87b/0xb20 kernel/workqueue.c:4485
 wg_destruct+0x19c/0x300 drivers/net/wireguard/device.c:239
 netdev_run_todo+0x82d/0xa40 net/core/dev.c:10691
 default_device_exit_batch+0x33b/0x390 net/core/dev.c:11668
 ops_exit_list net/core/net_namespace.c:177 [inline]
 cleanup_net+0x77b/0xb80 net/core/net_namespace.c:635
 process_one_work+0x863/0x1000 kernel/workqueue.c:2310
 worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457
 kthread+0x436/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>

Crashes (138):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/09/19 08:29 linux-5.15.y 43bb85222e53 e2beed91 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2025/09/01 01:22 linux-5.15.y 01879f56bdde 807a3b61 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2025/08/06 13:50 linux-5.15.y c79648372d02 ffe1dd46 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2025/06/02 09:15 linux-5.15.y 98f47d0e9b8c 3d2f584d .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2025/04/15 00:58 linux-5.15.y f7347f400572 0bd6db41 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 INFO: rcu detected stall in cleanup_net
2025/01/05 21:13 linux-5.15.y 91786f140358 f3558dbf .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 INFO: rcu detected stall in cleanup_net
2024/12/08 07:41 linux-5.15.y 0a51d2d4527b 9ac0fdc6 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 INFO: rcu detected stall in cleanup_net
2025/10/11 06:56 linux-5.15.y 29e53a5b1c4f ff1712fe .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2025/10/09 13:49 linux-5.15.y 29e53a5b1c4f 7e2882b3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2025/09/27 00:10 linux-5.15.y 43bb85222e53 001c9061 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2025/09/10 17:12 linux-5.15.y de9476bb4f1b fdeaa69b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2025/09/06 14:01 linux-5.15.y 7a6c2d093c45 d291dd2d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2025/09/03 10:00 linux-5.15.y 01879f56bdde 96a211bc .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in cleanup_net
2025/09/02 03:00 linux-5.15.y 01879f56bdde 807a3b61 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in cleanup_net
2025/08/30 23:55 linux-5.15.y 01879f56bdde 807a3b61 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2025/08/22 14:48 linux-5.15.y c79648372d02 bf27483f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2025/08/21 01:26 linux-5.15.y c79648372d02 0b9605c8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2025/08/18 07:56 linux-5.15.y c79648372d02 1804e95e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2025/08/05 20:10 linux-5.15.y c79648372d02 37880f40 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2025/07/31 15:13 linux-5.15.y c79648372d02 f8f2b4da .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2025/07/25 17:53 linux-5.15.y c79648372d02 fb8f743d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2025/07/18 23:24 linux-5.15.y c79648372d02 7117feec .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2025/07/18 09:46 linux-5.15.y c79648372d02 88248e14 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2025/07/11 14:26 linux-5.15.y 2f693b607545 3cda49cf .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2025/07/04 08:52 linux-5.15.y 3dea0e7f549e 76ad128c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2025/06/27 05:15 linux-5.15.y 1c700860e8bc 803ce19b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2025/06/25 01:43 linux-5.15.y 1c700860e8bc 26d77996 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2025/06/13 02:12 linux-5.15.y 1c700860e8bc 98683f8f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2025/06/12 21:38 linux-5.15.y 1c700860e8bc 98683f8f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2025/06/08 13:05 linux-5.15.y 1c700860e8bc 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2025/05/27 03:56 linux-5.15.y 98f47d0e9b8c 874a1386 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2025/05/25 14:27 linux-5.15.y 98f47d0e9b8c ed351ea7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2025/05/23 09:42 linux-5.15.y 98f47d0e9b8c fa44301a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2025/05/12 11:15 linux-5.15.y 3b8db0e4f263 77908e5f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2025/05/09 22:38 linux-5.15.y 3b8db0e4f263 77908e5f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2025/05/05 19:55 linux-5.15.y 16fdf2c7111b 6ca47dd8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2025/05/02 13:18 linux-5.15.y 16fdf2c7111b d7f099d1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2025/05/01 21:01 linux-5.15.y f7347f400572 51b137cd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2025/04/27 03:05 linux-5.15.y f7347f400572 c6b4fb39 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2025/04/27 03:03 linux-5.15.y f7347f400572 c6b4fb39 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2025/04/24 12:55 linux-5.15.y f7347f400572 9882047a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2025/04/24 11:15 linux-5.15.y f7347f400572 9882047a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2025/04/24 02:37 linux-5.15.y f7347f400572 73a168d0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2025/04/14 22:21 linux-5.15.y f7347f400572 0bd6db41 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2025/04/12 00:26 linux-5.15.y f7347f400572 0bd6db41 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2025/04/09 19:38 linux-5.15.y 0c935c049b5c 47d015b1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2025/04/05 10:47 linux-5.15.y 0c935c049b5c c53ea9c9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2025/03/28 10:49 linux-5.15.y 0c935c049b5c 6c09fb82 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2025/03/22 02:42 linux-5.15.y 0c935c049b5c c6512ef7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2025/03/20 09:34 linux-5.15.y 0c935c049b5c 9209bc22 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2025/03/19 01:29 linux-5.15.y 0c935c049b5c 22a6c2b1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2025/03/14 07:03 linux-5.15.y 0c935c049b5c e2826670 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2025/03/13 22:26 linux-5.15.y 0c935c049b5c 44be8b44 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2025/03/07 22:55 linux-5.15.y c16c81c81336 7e3bd60d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2023/07/11 05:03 linux-5.15.y d54cfc420586 52ae002a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
* Struck through repros no longer work on HEAD.