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INFO: rcu detected stall in gc_worker

Status: upstream: reported C repro on 2023/07/03 02:12
Bug presence: origin:upstream
[Documentation on labels]
Reported-by: syzbot+458308355e7401f2f4c5@syzkaller.appspotmail.com
First crash: 300d, last: 4d04h
▶ ▼ Bug presence (2)
Date Name Commit Repro Result
2023/07/05 upstream (ToT) d528014517f2 C [report] INFO: rcu detected stall in corrupted
2024/04/15 upstream (ToT) 0bbac3facb5d C Failed due to an error; will retry later
▶ ▼ 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 833d 871d 0/26 closed as invalid on 2022/02/08 10:33
upstream INFO: rcu detected stall in gc_worker (3) netfilter C done done 47 90d 770d 0/26 upstream: reported C repro on 2022/03/20 12:02
upstream INFO: rcu detected stall in gc_worker netfilter 8 1837d 1922d 0/26 auto-closed as invalid on 2019/10/14 16:34
linux-5.15 INFO: rcu detected stall in gc_worker origin:upstream C error 6 77d 265d 0/3 upstream: reported C repro on 2023/08/06 21:00
linux-4.19 INFO: rcu detected stall in gc_worker syz error 1 736d 736d 0/1 upstream: reported syz repro on 2022/04/22 15:43
▶ ▼ Fix bisection attempts (6)
Created Duration User Patch Repo Result
2024/04/24 07:31 2h33m bisect fix linux-6.1.y job log (0) log
2024/02/16 22:50 2h26m bisect fix linux-6.1.y job log (0) log
2024/01/07 17:15 2h06m bisect fix linux-6.1.y job log (0) log
2023/11/26 07:58 2h12m bisect fix linux-6.1.y job log (0) log
2023/10/24 21:30 2h00m bisect fix linux-6.1.y job log (0) log
2023/09/18 17:35 2h25m bisect fix linux-6.1.y job log (0) log

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (1 ticks this GP) idle=a214/1/0x4000000000000000 softirq=6559/6559 fqs=682
	(detected by 1, t=10504 jiffies, g=5701, q=1030 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 3596 Comm: kworker/0:4 Not tainted 6.1.82-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024
Workqueue: events_power_efficient gc_worker
RIP: 0010:mark_lock+0xe8/0x340 kernel/locking/lockdep.c:4606
Code: e8 03 42 0f b6 04 28 84 c0 0f 85 0f 02 00 00 83 3d ec 21 5e 10 00 74 39 31 db 48 83 c3 50 48 89 d8 48 c1 e8 03 42 80 3c 28 00 <74> 08 48 89 df e8 1e 39 77 00 41 bc 01 00 00 00 44 85 33 74 53 44
RSP: 0018:ffffc90000007a38 EFLAGS: 00000046
RAX: 1ffffffff203215e RBX: ffffffff90190af0 RCX: ffffffff816abf3a
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff90496228
RBP: 0000000000000000 R08: dffffc0000000000 R09: fffffbfff2092c46
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff88807bfbc658
R13: dffffc0000000000 R14: 0000000000000001 R15: ffff88807bfbc6d8
FS:  0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000002000009c CR3: 000000007e0bc000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 mark_usage kernel/locking/lockdep.c:4520 [inline]
 __lock_acquire+0xb40/0x1f80 kernel/locking/lockdep.c:5003
 lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662
 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:119 [inline]
 _raw_spin_lock_irq+0xcf/0x110 kernel/locking/spinlock.c:170
 __run_hrtimer kernel/time/hrtimer.c:1690 [inline]
 __hrtimer_run_queues+0x6d3/0xe50 kernel/time/hrtimer.c:1750
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1812
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1095 [inline]
 __sysvec_apic_timer_interrupt+0x156/0x580 arch/x86/kernel/apic/apic.c:1112
 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1106
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:653
RIP: 0010:lock_acquire+0x26f/0x5a0 kernel/locking/lockdep.c:5666
Code: 2b 00 74 08 4c 89 f7 e8 2f a5 77 00 f6 44 24 61 02 0f 85 84 01 00 00 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 44 25 00 00 00 00 00 43 c7 44 25 09 00 00 00 00 43 c7 44 25
RSP: 0018:ffffc90003baf9a0 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 1ffff92000775f40 RCX: 1ffff92000775ee0
RDX: dffffc0000000000 RSI: ffffffff8aebffc0 RDI: ffffffff8b3d2b40
RBP: ffffc90003bafae8 R08: dffffc0000000000 R09: fffffbfff2092c45
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff92000775f3c
R13: dffffc0000000000 R14: ffffc90003bafa00 R15: 0000000000000246
 rcu_lock_acquire include/linux/rcupdate.h:319 [inline]
 rcu_read_lock include/linux/rcupdate.h:760 [inline]
 gc_worker+0x29b/0x1530 net/netfilter/nf_conntrack_core.c:1501
 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292
 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:307
 </TASK>
INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.820 msecs
rcu: rcu_preempt kthread starved for 7094 jiffies! g5701 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:27032 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5245 [inline]
 __schedule+0x142d/0x4550 kernel/sched/core.c:6558
 schedule+0xbf/0x180 kernel/sched/core.c:6634
 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1935
 rcu_gp_fqs_loop+0x2d2/0x1120 kernel/rcu/tree.c:1706
 rcu_gp_kthread+0xa3/0x3a0 kernel/rcu/tree.c:1905
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:307
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 PID: 11 Comm: kworker/u4:1 Not tainted 6.1.82-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x60 kernel/kcov.c:203
Code: e8 25 00 00 00 0f 0b 0f 1f 00 53 48 89 fb e8 17 00 00 00 48 8b 3d 58 e1 e8 0c 48 89 de 5b e9 37 9e 56 00 cc cc cc cc cc cc cc <48> 8b 04 24 65 48 8b 0d a4 eb 77 7e 65 8b 15 a5 eb 77 7e f7 c2 00
RSP: 0018:ffffc90000107598 EFLAGS: 00000202
RAX: 0000000000000000 RBX: 1ffff1101730859d RCX: ffff88813febbb80
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90000107980 R08: ffffffff817f4404 R09: fffffbfff2092c45
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000800000000
R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8880b9842ce8
FS:  0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555555ee36f8 CR3: 000000000ce8e000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 </IRQ>
 <TASK>
 csd_lock_wait kernel/smp.c:424 [inline]
 smp_call_function_many_cond+0x1fcb/0x3460 kernel/smp.c:998
 on_each_cpu_cond_mask+0x3b/0x80 kernel/smp.c:1166
 on_each_cpu include/linux/smp.h:71 [inline]
 text_poke_sync arch/x86/kernel/alternative.c:1334 [inline]
 text_poke_bp_batch+0x2bb/0x940 arch/x86/kernel/alternative.c:1534
 text_poke_flush arch/x86/kernel/alternative.c:1725 [inline]
 text_poke_finish+0x16/0x30 arch/x86/kernel/alternative.c:1732
 arch_jump_label_transform_apply+0x13/0x20 arch/x86/kernel/jump_label.c:146
 static_key_enable_cpuslocked+0x12e/0x250 kernel/jump_label.c:177
 static_key_enable+0x16/0x20 kernel/jump_label.c:190
 toggle_allocation_gate+0xbf/0x480 mm/kfence/core.c:804
 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292
 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:307
 </TASK>

Crashes (7):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/03/24 18:18 linux-6.1.y d7543167affd 0ea90952 .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in gc_worker
2024/02/24 05:36 linux-6.1.y 81e1dc2f7001 8d446f15 .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in gc_worker
2023/07/03 08:44 linux-6.1.y 0f4ac6b4c5f0 bfc47836 .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in gc_worker
2023/07/03 02:12 linux-6.1.y 0f4ac6b4c5f0 bfc47836 .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in gc_worker
2024/02/21 16:35 linux-6.1.y 8b4118fabd6e 3af7dd65 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in gc_worker
2023/12/08 15:51 linux-6.1.y 6c6a6c7e211c 28b24332 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in gc_worker
2023/12/07 11:55 linux-6.1.y c6114c845984 0a02ce36 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in gc_worker
* Struck through repros no longer work on HEAD.