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INFO: rcu detected stall in cleanup_net

Status: upstream: reported syz repro on 2023/07/11 05:04
Bug presence: origin:upstream
[Documentation on labels]
Reported-by: syzbot+f5d4d279dfe9b422732e@syzkaller.appspotmail.com
First crash: 777d, last: 4d06h
▶ ▼ Bug presence (1)
Date Name Commit Repro Result
2025/06/02 upstream (ToT) d00a83477e7a syz [report] INFO: rcu detected stall in tc_modify_qdisc
▶ ▼ 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 2171d 2171d 0/29 auto-closed as invalid on 2019/12/15 02:54
upstream INFO: rcu detected stall in cleanup_net (6) net 1 63 718d 961d 0/29 closed as invalid on 2023/10/27 14:39
linux-4.19 INFO: rcu detected stall in cleanup_net (2) 1 4 1521d 1653d 0/1 auto-closed as invalid on 2021/10/25 03:43
upstream INFO: rcu detected stall in cleanup_net kernel 1 5 2603d 2671d 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 1816d 1812d 15/29 fixed on 2020/10/10 01:52
upstream INFO: rcu detected stall in cleanup_net (5) net 1 24 1299d 1559d 0/29 closed as invalid on 2022/02/08 10:00
linux-4.19 INFO: rcu detected stall in cleanup_net 1 1 2043d 2043d 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 140 290d 776d 0/3 upstream: reported syz repro on 2023/07/12 14:45
upstream INFO: rcu detected stall in cleanup_net (2) kernel 1 1 2514d 2510d 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 272d 649d 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 110d 110d 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 905d 1017d 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 351d 478d 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 221d 221d 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 1151d 1364d 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: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P154/1:b..l
	(detected by 0, t=10503 jiffies, g=7917, q=277)
task:kworker/u4:2    state:R  running task     stack:22888 pid:  154 ppid:     2 flags:0x00004000
Workqueue: netns cleanup_net
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5030 [inline]
 __schedule+0x11b8/0x43b0 kernel/sched/core.c:6376
 preempt_schedule_irq+0xb1/0x150 kernel/sched/core.c:6780
 irqentry_exit+0x63/0x70 kernel/entry/common.c:432
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:lock_acquire+0x1f2/0x3f0 kernel/locking/lockdep.c:5627
Code: 00 9c 8f 84 24 80 00 00 00 f6 84 24 81 00 00 00 02 0f 85 f6 00 00 00 41 f7 c6 00 02 00 00 74 01 fb 48 c7 44 24 60 0e 36 e0 45 <4b> c7 44 3d 00 00 00 00 00 66 43 c7 44 3d 09 00 00 43 c6 44 3d 0b
RSP: 0018:ffffc90001fc7900 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 0000000000000000 RCX: f7491a2ba11c6a00
RDX: 0000000000000000 RSI: ffffffff8a0b2860 RDI: ffffffff8a599340
RBP: ffffc90001fc7a20 R08: dffffc0000000000 R09: fffffbfff1ff6e19
R10: fffffbfff1ff6e19 R11: 1ffffffff1ff6e18 R12: ffffffff8c11c360
R13: 1ffff920003f8f2c R14: 0000000000000246 R15: dffffc0000000000
 rcu_lock_acquire+0x2a/0x30 include/linux/rcupdate.h:312
 rcu_read_lock include/linux/rcupdate.h:739 [inline]
 inet_twsk_purge+0x119/0x810 net/ipv4/inet_timewait_sock.c:268
 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>
rcu: rcu_preempt kthread starved for 10534 jiffies! g7917 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0
rcu: 	Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt     state:R  running task     stack:28032 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5030 [inline]
 __schedule+0x11b8/0x43b0 kernel/sched/core.c:6376
 schedule+0x11b/0x1e0 kernel/sched/core.c:6459
 schedule_timeout+0x15c/0x280 kernel/time/timer.c:1914
 rcu_gp_fqs_loop+0x29e/0x11b0 kernel/rcu/tree.c:1972
 rcu_gp_kthread+0x98/0x350 kernel/rcu/tree.c:2145
 kthread+0x436/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
NMI backtrace for cpu 0
CPU: 0 PID: 4380 Comm: syz.4.21 Not tainted 5.15.189-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
 <IRQ>
 dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x397/0x3d0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline]
 rcu_check_gp_kthread_starvation+0x1cd/0x250 kernel/rcu/tree_stall.h:487
 print_other_cpu_stall+0x10c8/0x1220 kernel/rcu/tree_stall.h:592
 check_cpu_stall kernel/rcu/tree_stall.h:745 [inline]
 rcu_pending kernel/rcu/tree.c:3936 [inline]
 rcu_sched_clock_irq+0x831/0x1110 kernel/rcu/tree.c:2619
 update_process_times+0x193/0x200 kernel/time/timer.c:1818
 tick_sched_handle kernel/time/tick-sched.c:254 [inline]
 tick_sched_timer+0x37d/0x560 kernel/time/tick-sched.c:1473
 __run_hrtimer kernel/time/hrtimer.c:1690 [inline]
 __hrtimer_run_queues+0x4fe/0xc40 kernel/time/hrtimer.c:1754
 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:__syscall_enter_from_user_work kernel/entry/common.c:93 [inline]
RIP: 0010:syscall_enter_from_user_mode+0x2a/0x70 kernel/entry/common.c:114
Code: 41 56 53 48 89 f3 49 89 fe 48 8b 7c 24 10 e8 3d f6 ff ff eb 31 eb 35 e8 84 ab d5 f7 e8 7f a9 d5 f7 fb 65 48 8b 05 06 37 5a 76 <48> 8b 70 08 40 f6 c6 3f 74 0b 4c 89 f7 5b 41 5e e9 f1 ee bd f7 48
RSP: 0018:ffffc90003f8ff08 EFLAGS: 00000286
RAX: ffff88807b7e8000 RBX: 0000000000000027 RCX: 4b7514403cf70500
RDX: dffffc0000000000 RSI: ffffffff8a0b15c0 RDI: ffffffff8a599340
RBP: ffffc90003f8ff48 R08: dffffc0000000000 R09: fffffbfff1ad2dd6
R10: fffffbfff1ad2dd6 R11: 1ffffffff1ad2dd5 R12: 0000000000000000
R13: 0000000000000000 R14: ffffc90003f8ff58 R15: 0000000000000000
 do_syscall_64+0x24/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fab8e45aba7
Code: 0b e9 68 fe ff ff 48 83 c4 18 48 8d 3d f2 6c d6 00 5b 5d 41 5c 41 5d 41 5e 41 5f e9 f3 f7 fb ff 0f 1f 00 b8 27 00 00 00 0f 05 <c3> 0f 1f 84 00 00 00 00 00 b8 6e 00 00 00 0f 05 c3 0f 1f 84 00 00
RSP: 002b:00007ffe3e830448 EFLAGS: 00000206 ORIG_RAX: 0000000000000027
RAX: ffffffffffffffda RBX: 00007ffe3e8305b0 RCX: 00007fab8e45aba7
RDX: 00007ffe3e830480 RSI: 00007ffe3e8305b0 RDI: 0000000000000021
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 00007fab8e68afa0 R14: 00007fab8e68afa0 R15: 0000000000000004
 </TASK>

Crashes (126):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
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
2025/08/22 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
2025/03/06 17:47 linux-5.15.y c16c81c81336 831e3629 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2025/02/28 12:13 linux-5.15.y c16c81c81336 6a8fcbc4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2025/02/24 01:47 linux-5.15.y c16c81c81336 d34966d1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2025/02/20 02:50 linux-5.15.y c16c81c81336 b257a9b7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2025/02/14 20:14 linux-5.15.y c16c81c81336 1022af74 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2025/02/13 20:08 linux-5.15.y c16c81c81336 a98a8417 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in cleanup_net
2025/02/03 14:31 linux-5.15.y c16c81c81336 a21a8419 .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.