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: 1180d, last: 4d11h
▶ ▼ 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 (16)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in cleanup_net (8) prio:normal kernfs 1 syz, C error inconclusive 37 33d 262d 0/29 upstream: reported C repro on 2026/01/13 16:49
upstream INFO: rcu detected stall in cleanup_net (3) net 1 1 2574d 2574d 0/29 auto-closed as invalid on 2019/12/15 02:54
upstream INFO: rcu detected stall in cleanup_net (6) net 1 63 1121d 1364d 0/29 closed as invalid on 2023/10/27 14:39
linux-4.19 INFO: rcu detected stall in cleanup_net (2) 1 4 1924d 2056d 0/1 auto-closed as invalid on 2021/10/25 03:43
upstream INFO: rcu detected stall in cleanup_net kernel 1 5 3006d 3074d 0/29 closed as invalid on 2018/09/05 12:51
upstream INFO: rcu detected stall in cleanup_net (4) kernel 1 syz, C done 5 2219d 2215d 15/29 fixed on 2020/10/10 01:52
upstream INFO: rcu detected stall in cleanup_net (5) net 1 24 1702d 1962d 0/29 closed as invalid on 2022/02/08 10:00
linux-4.19 INFO: rcu detected stall in cleanup_net 1 1 2446d 2446d 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 143 223d 1178d 0/3 upstream: reported syz repro on 2023/07/12 14:45
upstream INFO: rcu detected stall in cleanup_net (2) kernel 1 1 2917d 2913d 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 674d 1052d 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 512d 512d 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 syz, C 3 1307d 1420d 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 754d 880d 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 624d 624d 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 1553d 1766d 0/1 auto-obsoleted due to no activity on 2022/10/30 18:15
▶ ▼ Last patch testing requests (10)
Created Duration User Patch Repo Result
2026/03/19 14:16 11m retest repro linux-5.15.y error
2026/03/19 14:16 11m retest repro linux-5.15.y error
2026/03/19 14:16 11m retest repro linux-5.15.y error
2026/03/19 14:16 8m retest repro linux-5.15.y error
2026/03/19 14:16 46m retest repro linux-5.15.y error
2026/03/19 05:50 16m retest repro linux-5.15.y report log
2026/03/19 05:50 19m retest repro linux-5.15.y report log
2026/03/19 05:50 12m retest repro linux-5.15.y report log
2026/03/19 00:47 11m retest repro linux-5.15.y report log
2026/03/19 00:47 12m retest repro linux-5.15.y report log
▶ ▼ Fix bisection attempts (4)
Created Duration User Patch Repo Result
2025/11/10 04:20 2h06m fix candidate upstream OK (0) job log
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=187/1/0x4000000000000000 softirq=7264/7265 fqs=5240 
	(detected by 0, t=10502 jiffies, g=7717, q=11949)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 3081 Comm: kworker/u4:5 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Workqueue: netns cleanup_net
RIP: 0010:lockdep_enabled kernel/locking/lockdep.c:91 [inline]
RIP: 0010:lock_acquire+0x11f/0x400 kernel/locking/lockdep.c:5601
Code: 65 8b 05 e4 8b a5 7e 85 c0 0f 85 43 01 00 00 65 4c 8b 35 54 82 a5 7e 49 81 c6 ec 0a 00 00 4c 89 f0 48 c1 e8 03 42 0f b6 04 38 <84> c0 0f 85 08 02 00 00 41 83 3e 00 0f 85 16 01 00 00 43 c6 44 3d
RSP: 0018:ffffc90000dd0ba0 EFLAGS: 00000803
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 4fb5d7e81bb69d00
RDX: 0000000000000000 RSI: ffffffff8a7a48a0 RDI: ffffffff8a7a4860
RBP: ffffc90000dd0ca8 R08: ffffffff8d8b1eef R09: 1ffffffff1b163dd
R10: dffffc0000000000 R11: fffffbfff1b163de R12: ffff8880b912a258
R13: 1ffff920001ba180 R14: ffff88802ae5a8ac R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000000300 CR3: 000000007af7f000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:128 [inline]
 _raw_spin_lock_irq+0xab/0xf0 kernel/locking/spinlock.c:170
 __run_hrtimer kernel/time/hrtimer.c:1689 [inline]
 __hrtimer_run_queues+0x59a/0xb60 kernel/time/hrtimer.c:1749
 hrtimer_interrupt+0x397/0x8b0 kernel/time/hrtimer.c:1811
 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_enabled kernel/locking/lockdep.c:91 [inline]
RIP: 0010:lock_acquire+0x10c/0x400 kernel/locking/lockdep.c:5601
Code: 0f 85 1c 02 00 00 83 3d 35 65 2e 0c 00 0f 84 0a 01 00 00 65 8b 05 e4 8b a5 7e 85 c0 0f 85 43 01 00 00 65 4c 8b 35 54 82 a5 7e <49> 81 c6 ec 0a 00 00 4c 89 f0 48 c1 e8 03 42 0f b6 04 38 84 c0 0f
RSP: 0018:ffffc9000d92f920 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 4fb5d7e81bb69d00
RDX: 0000000000000000 RSI: ffffffff8a7a48a0 RDI: ffffffff8a7a4860
RBP: ffffc9000d92fa40 R08: ffffffff8d8b1eef R09: 1ffffffff1b163dd
R10: dffffc0000000000 R11: fffffbfff1b163de R12: ffffffff8c31ef60
R13: 1ffff92001b25f30 R14: ffff88802ae59dc0 R15: dffffc0000000000
 rcu_lock_acquire+0x2a/0x30 include/linux/rcupdate.h:313
 rcu_read_lock include/linux/rcupdate.h:740 [inline]
 inet_twsk_purge+0x10d/0x820 net/ipv4/inet_timewait_sock.c:268
 ops_exit_list net/core/net_namespace.c:177 [inline]
 cleanup_net+0x78e/0xba0 net/core/net_namespace.c:635
 process_one_work+0x867/0xff0 kernel/workqueue.c:2310
 worker_thread+0xad7/0x12a0 kernel/workqueue.c:2457
 kthread+0x42e/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>

Crashes (203):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/09/19 01:45 linux-5.15.y 0248c33e835e 853b104b .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2026/02/15 10:06 linux-5.15.y e45d5d41c134 1e62d198 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2025/10/26 08:21 linux-5.15.y ac56c046adf4 c0460fcd .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2025/10/25 14:58 linux-5.15.y ac56c046adf4 c0460fcd .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2025/09/19 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
2026/02/21 10:26 linux-5.15.y 3330a8d33e08 6e7b5511 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2026/01/09 05:52 linux-5.15.y 68efe5a6c16a d6526ea3 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2025/12/10 14:33 linux-5.15.y 68efe5a6c16a d6526ea3 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in cleanup_net
2025/11/02 13:13 linux-5.15.y cc5ec8769306 2c50b6a9 .config console log report syz / log [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
2026/09/28 23:00 linux-5.15.y 0248c33e835e a3c7249d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in cleanup_net
2026/09/26 16:43 linux-5.15.y 0248c33e835e a3c7249d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in cleanup_net
2026/09/23 13:18 linux-5.15.y 0248c33e835e abce1216 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in cleanup_net
2026/09/13 15:59 linux-5.15.y 0996e0926f6b 70a60e12 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in cleanup_net
2026/09/07 17:05 linux-5.15.y 0996e0926f6b 680aa3e1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2026/09/05 05:22 linux-5.15.y 0996e0926f6b 4f7b22a0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2026/09/04 20:22 linux-5.15.y 0996e0926f6b f65209a4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2026/08/30 16:15 linux-5.15.y 28c35638ec51 2f52988a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in cleanup_net
2026/08/20 17:00 linux-5.15.y 0eb903b5b519 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in cleanup_net
2026/08/11 01:14 linux-5.15.y aabd761612db 508909ea .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2026/08/05 06:16 linux-5.15.y 6e2fd6534337 52aa2820 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2026/07/31 16:02 linux-5.15.y 6e2fd6534337 7664cf44 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in cleanup_net
2026/07/20 13:57 linux-5.15.y c86c4726e7f0 de6a700d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in cleanup_net
2026/07/06 18:15 linux-5.15.y c86c4726e7f0 88b240e4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2026/06/26 01:41 linux-5.15.y eceeec79dbc6 7ff32d8b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2026/06/16 01:25 linux-5.15.y dc027a595035 50bb0618 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in cleanup_net
2026/06/15 11:10 linux-5.15.y dc027a595035 1d2f3589 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2026/05/28 04:01 linux-5.15.y 241d66fa280c 4c36e7e5 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2026/05/07 09:41 linux-5.15.y ef251c45f1cd f250db59 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2026/05/05 03:26 linux-5.15.y ef251c45f1cd a898ba9c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2026/04/12 18:40 linux-5.15.y 91d48252ad4b 38c8e246 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2026/03/04 21:02 linux-5.15.y 91d48252ad4b e6b6b96b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in cleanup_net
2026/02/24 06:28 linux-5.15.y 3330a8d33e08 41d2fa6a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2026/02/24 04:05 linux-5.15.y 3330a8d33e08 41d2fa6a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2026/02/21 19:13 linux-5.15.y 3330a8d33e08 6e7b5511 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2026/02/21 15:08 linux-5.15.y 3330a8d33e08 6e7b5511 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2026/02/21 06:55 linux-5.15.y 3330a8d33e08 6e7b5511 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2026/02/15 12:43 linux-5.15.y e45d5d41c134 1e62d198 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2026/02/12 04:08 linux-5.15.y e45d5d41c134 76a109e2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2026/02/11 23:32 linux-5.15.y e45d5d41c134 75707236 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2026/02/07 06:09 linux-5.15.y 7b232985052f f20fc9f9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2026/01/29 17:18 linux-5.15.y 9eec9a14ee10 aeb6fdd5 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2026/01/26 05:11 linux-5.15.y 9eec9a14ee10 55756628 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2026/01/25 09:40 linux-5.15.y 9eec9a14ee10 40acda8a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2026/01/24 22:25 linux-5.15.y 9eec9a14ee10 40acda8a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2026/01/23 03:58 linux-5.15.y 9eec9a14ee10 82c9c083 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2026/01/21 03:22 linux-5.15.y 9eec9a14ee10 06648d9c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2026/01/20 06:46 linux-5.15.y 9eec9a14ee10 572effc1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2026/01/15 23:15 linux-5.15.y 68efe5a6c16a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2026/01/05 13:03 linux-5.15.y 68efe5a6c16a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2026/01/03 05:12 linux-5.15.y 68efe5a6c16a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2026/01/01 01:10 linux-5.15.y 68efe5a6c16a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2025/12/28 13:03 linux-5.15.y 68efe5a6c16a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in cleanup_net
2025/12/27 01:30 linux-5.15.y 68efe5a6c16a d6526ea3 .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.