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INFO: rcu detected stall in gc_worker

Status: upstream: reported C repro on 2023/08/06 21:00
Bug presence: origin:upstream
[Documentation on labels]
Reported-by: syzbot+c6ab59ecefe93f5cab03@syzkaller.appspotmail.com
First crash: 541d, last: 8d03h
Fix bisection: failed (error log, bisect log)
  
▶ ▼ Bug presence (1)
Date Name Commit Repro Result
2023/08/07 upstream (ToT) 52a93d39b17d C [report] INFO: rcu detected stall in corrupted
▶ ▼ Similar bugs (5)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in gc_worker (2) netfilter C unreliable 4 1108d 1146d 0/28 closed as invalid on 2022/02/08 10:33
upstream INFO: rcu detected stall in gc_worker (3) netfilter C done done 126 1d02h 1045d 0/28 upstream: reported C repro on 2022/03/20 12:02
upstream INFO: rcu detected stall in gc_worker netfilter 8 2113d 2198d 0/28 auto-closed as invalid on 2019/10/14 16:34
linux-6.1 INFO: rcu detected stall in gc_worker origin:upstream C 63 17d 575d 0/3 upstream: reported C repro on 2023/07/03 02:12
linux-4.19 INFO: rcu detected stall in gc_worker syz error 1 1012d 1012d 0/1 upstream: reported syz repro on 2022/04/22 15:43
▶ ▼ Last patch testing requests (9)
Created Duration User Patch Repo Result
2025/01/16 12:08 18m retest repro linux-5.15.y report log
2025/01/16 12:08 20m retest repro linux-5.15.y report log
2025/01/16 12:08 20m retest repro linux-5.15.y report log
2025/01/16 12:08 20m retest repro linux-5.15.y report log
2025/01/16 12:08 12m retest repro linux-5.15.y report log
2025/01/16 10:32 14m retest repro linux-5.15.y report log
2025/01/16 10:32 18m retest repro linux-5.15.y error
2025/01/16 10:32 15m retest repro linux-5.15.y report log
2025/01/16 10:32 14m retest repro linux-5.15.y report log
▶ ▼ Fix bisection attempts (4)
Created Duration User Patch Repo Result
2024/03/16 14:35 18m bisect fix linux-5.15.y error job log
2024/01/19 00:07 2h02m bisect fix linux-5.15.y OK (0) job log log
2023/11/27 09:09 1h53m bisect fix linux-5.15.y OK (0) job log log
2023/10/04 20:45 1h54m bisect fix linux-5.15.y OK (0) job log log

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P7/1:b..l
	(detected by 0, t=10502 jiffies, g=5521, q=54)
task:kworker/0:0     state:R  running task     stack:27936 pid:    7 ppid:     2 flags:0x00004000
Workqueue: events_power_efficient gc_worker
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5027 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373
 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6777
 irqentry_exit+0x53/0x80 kernel/entry/common.c:432
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:seqcount_lockdep_reader_access+0x1dc/0x220 include/linux/seqlock.h:106
Code: f8 4d 85 ed 75 16 e8 e3 8f e5 f8 eb 15 e8 dc 8f e5 f8 e8 27 fa a3 01 4d 85 ed 74 ea e8 cd 8f e5 f8 fb 48 c7 04 24 0e 36 e0 45 <4b> c7 04 3c 00 00 00 00 66 43 c7 44 3c 09 00 00 43 c6 44 3c 0b 00
RSP: 0018:ffffc90000cc7a40 EFLAGS: 00000293
RAX: ffffffff889af513 RBX: 0000000000000000 RCX: ffff888017693b80
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90000cc7af0 R08: ffffffff889af4e9 R09: fffffbfff2131234
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: 0000000000000200 R14: 0000000000000046 R15: 1ffff92000198f48
 nf_conntrack_get_ht include/net/netfilter/nf_conntrack.h:338 [inline]
 gc_worker+0x30f/0x14b0 net/netfilter/nf_conntrack_core.c:1472
 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
rcu: rcu_preempt kthread starved for 10528 jiffies! g5521 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
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:27064 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5027 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373
 schedule+0x11b/0x1f0 kernel/sched/core.c:6456
 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1914
 rcu_gp_fqs_loop+0x2bf/0x1080 kernel/rcu/tree.c:1972
 rcu_gp_kthread+0xa4/0x360 kernel/rcu/tree.c:2145
 kthread+0x3f6/0x4f0 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:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 4204 Comm: syz-executor185 Not tainted 5.15.175-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:__kasan_check_read+0x6/0x10 mm/kasan/shadow.c:31
Code: 41 5e 41 5f 5d c3 48 c7 c7 77 ef 3c 8c eb 0a 48 c7 c7 af ef 3c 8c 4c 89 fe e8 46 60 73 08 31 db eb d7 cc cc 89 f6 48 8b 0c 24 <31> d2 e9 63 ef ff ff 0f 1f 00 89 f6 48 8b 0c 24 ba 01 00 00 00 e9
RSP: 0018:ffffc90000dd0b38 EFLAGS: 00000002
RAX: 0000000000000001 RBX: 0000000000000045 RCX: ffffffff8162d879
RDX: dffffc0000000000 RSI: 0000000000000008 RDI: ffffffff90989108
RBP: 0000000000000000 R08: dffffc0000000000 R09: fffffbfff2131222
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000000
R13: ffff88807e518ae8 R14: 0000000000000000 R15: ffff88807e518b10
FS:  000055555fc453c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000002006b000 CR3: 000000001bba6000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 instrument_atomic_read include/linux/instrumented.h:71 [inline]
 test_bit include/asm-generic/bitops/instrumented-non-atomic.h:134 [inline]
 hlock_class kernel/locking/lockdep.c:197 [inline]
 check_wait_context kernel/locking/lockdep.c:4687 [inline]
 __lock_acquire+0x549/0x1ff0 kernel/locking/lockdep.c:4962
 lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
 seqcount_lockdep_reader_access+0xf8/0x220 include/linux/seqlock.h:103
 timekeeping_get_delta kernel/time/timekeeping.c:254 [inline]
 timekeeping_get_ns kernel/time/timekeeping.c:388 [inline]
 ktime_get+0x7f/0x270 kernel/time/timekeeping.c:831
 clockevents_program_event+0xe1/0x310 kernel/time/clockevents.c:326
 hrtimer_interrupt+0x546/0x980 kernel/time/hrtimer.c:1827
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline]
 __sysvec_apic_timer_interrupt+0x13b/0x4b0 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:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:169 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x25/0x40 kernel/locking/spinlock.c:202
Code: 31 61 f6 ff 90 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 1e 65 1a f7 48 89 df e8 76 b9 1b f7 e8 21 75 3e f7 fb bf 01 00 00 00 <e8> 96 fe 0e f7 65 8b 05 a7 e1 b9 75 85 c0 74 02 5b c3 e8 74 fe b7
RSP: 0018:ffffc90002fdfbc0 EFLAGS: 00000282
RAX: b2f5972a0e1ece00 RBX: ffff88802b42ae40 RCX: ffffffff96a8ff03
RDX: dffffc0000000000 RSI: ffffffff8aab2b80 RDI: 0000000000000001
RBP: 0000000000000000 R08: ffffffff81870360 R09: ffffed10056855c9
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000021
R13: dffffc0000000000 R14: ffff88802b42b2d8 R15: ffff88802b42ae40
 spin_unlock_irq include/linux/spinlock.h:413 [inline]
 get_signal+0x13ee/0x14e0 kernel/signal.c:2903
 arch_do_signal_or_restart+0xc3/0x1890 arch/x86/kernel/signal.c:867
 handle_signal_work kernel/entry/common.c:154 [inline]
 exit_to_user_mode_loop+0x97/0x130 kernel/entry/common.c:178
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214
 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
 syscall_exit_to_user_mode+0x5d/0x240 kernel/entry/common.c:307
 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fd672c13859
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 11 19 00 00 90 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 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffe481223f8 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 0000000000000003 RCX: 00007fd672c13859
RDX: 000000002006b000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 00007fd672bd3990 R09: 00007fd672bd3990
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fd672c7131c
R13: 00007fd672c6b106 R14: 00007ffe48122430 R15: 0000000000000000
 </TASK>
INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.344 msecs
sched: RT throttling activated

Crashes (51):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/01/02 09:55 linux-5.15.y 91786f140358 d3ccff63 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in gc_worker
2024/10/18 05:59 linux-5.15.y 584a40a22cb9 666f77ed .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in gc_worker
2024/02/11 11:46 linux-5.15.y 6139f2a02fe0 77b23aa1 .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in gc_worker
2023/08/06 21:00 linux-5.15.y 38d4ca22a528 4ffcc9ef .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in gc_worker
2024/11/02 13:59 linux-5.15.y 72244eab0dad f00eed24 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in gc_worker
2024/10/30 07:17 linux-5.15.y 74cdd62cb470 66aeb999 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in gc_worker
2024/10/16 16:12 linux-5.15.y 3a5928702e71 bde2d81c .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in gc_worker
2024/09/27 13:18 linux-5.15.y 3a5928702e71 9314348a .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in gc_worker
2024/09/21 03:18 linux-5.15.y 3a5928702e71 6f888b75 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in gc_worker
2024/09/06 13:49 linux-5.15.y 14e468424d3e 464ac2ed .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in gc_worker
2024/08/31 10:37 linux-5.15.y fa93fa65db6e 1eda0d14 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in gc_worker
2024/09/20 16:59 linux-5.15.y 3a5928702e71 6f888b75 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 INFO: rcu detected stall in gc_worker
2025/01/20 20:01 linux-5.15.y 4735586da88e 6e87cfa2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in gc_worker
2024/12/24 02:04 linux-5.15.y 91786f140358 444551c4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in gc_worker
2024/12/14 00:58 linux-5.15.y 0a51d2d4527b 7cbfbb3a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in gc_worker
2024/12/13 11:24 linux-5.15.y 0a51d2d4527b 3547e30f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in gc_worker
2024/11/29 23:09 linux-5.15.y 0a51d2d4527b 5df23865 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in gc_worker
2024/11/26 03:40 linux-5.15.y 0a51d2d4527b 11dbc254 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in gc_worker
2024/11/14 11:49 linux-5.15.y 3c17fc483905 a8c99394 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in gc_worker
2024/11/04 21:23 linux-5.15.y 72244eab0dad 509da429 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in gc_worker
2024/10/28 06:53 linux-5.15.y 74cdd62cb470 65e8686b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in gc_worker
2024/10/26 05:40 linux-5.15.y 74cdd62cb470 65e8686b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in gc_worker
2024/10/19 07:02 linux-5.15.y 584a40a22cb9 cd6fc0a3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in gc_worker
2024/10/16 01:31 linux-5.15.y 3a5928702e71 bde2d81c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in gc_worker
2024/10/13 05:20 linux-5.15.y 3a5928702e71 084d8178 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in gc_worker
2024/10/11 16:04 linux-5.15.y 3a5928702e71 cd942402 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in gc_worker
2024/09/20 06:25 linux-5.15.y 3a5928702e71 6f888b75 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in gc_worker
2024/09/19 05:04 linux-5.15.y 3a5928702e71 c673ca06 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in gc_worker
2024/09/15 00:56 linux-5.15.y 3a5928702e71 08d8a733 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in gc_worker
2024/09/05 19:46 linux-5.15.y 14e468424d3e 464ac2ed .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in gc_worker
2024/09/05 15:07 linux-5.15.y 14e468424d3e 464ac2ed .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in gc_worker
2024/08/31 22:23 linux-5.15.y fa93fa65db6e 1eda0d14 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in gc_worker
2024/08/26 19:57 linux-5.15.y fa93fa65db6e 9aee4e0b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in gc_worker
2024/08/23 19:27 linux-5.15.y fa93fa65db6e d7d32352 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in gc_worker
2024/08/13 05:07 linux-5.15.y 7e89efd3ae1c 7b0f4b46 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in gc_worker
2024/07/23 07:41 linux-5.15.y 7c6d66f0266f 708c10c4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in gc_worker
2024/07/22 01:54 linux-5.15.y 7c6d66f0266f b88348e9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in gc_worker
2024/07/11 21:55 linux-5.15.y f45bea23c39c eaeb5c15 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in gc_worker
2024/07/11 09:40 linux-5.15.y f45bea23c39c c699c2eb .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in gc_worker
2024/07/04 19:59 linux-5.15.y 4878aadf2d15 3f2748a3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in gc_worker
2024/06/19 11:08 linux-5.15.y 4878aadf2d15 41b7e219 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in gc_worker
2024/06/17 01:07 linux-5.15.y 4878aadf2d15 f429ab00 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in gc_worker
2024/06/13 05:04 linux-5.15.y c61bd26ae81a 2aa5052f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in gc_worker
2024/05/17 14:29 linux-5.15.y 83655231580b a12e99e7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in gc_worker
2023/12/18 20:16 linux-5.15.y d0fc081c6241 924661f4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in gc_worker
2023/12/12 15:43 linux-5.15.y 8a1d809b0545 ebcad15c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in gc_worker
2023/10/26 16:58 linux-5.15.y 12952a23a5da 23afc60f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in gc_worker
2024/11/15 02:03 linux-5.15.y d98fd109f827 a8c99394 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 INFO: rcu detected stall in gc_worker
2024/08/05 07:22 linux-5.15.y 7e89efd3ae1c 1786a2a8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 INFO: rcu detected stall in gc_worker
2024/07/19 21:34 linux-5.15.y 7c6d66f0266f 890ce4f3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 INFO: rcu detected stall in gc_worker
2024/01/21 21:46 linux-5.15.y ddcaf4999061 9bd8dcda .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 INFO: rcu detected stall in gc_worker
* Struck through repros no longer work on HEAD.