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INFO: rcu detected stall in neigh_periodic_work (2)

Status: closed as invalid on 2024/03/13 18:06
Subsystems: net
[Documentation on labels]
First crash: 761d, last: 588d
Cause bisection: failed (error log, bisect log)
  
▶ ▼ Similar bugs (5)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in neigh_periodic_work (4) net 1 1 170d 170d 0/29 auto-obsoleted due to no activity on 2025/07/31 09:55
upstream BUG: soft lockup in neigh_periodic_work net 1 2 291d 323d 0/29 closed as invalid on 2025/01/28 16:26
upstream INFO: rcu detected stall in neigh_periodic_work (3) net 1 2 525d 545d 0/29 auto-obsoleted due to no activity on 2024/08/09 21:19
upstream INFO: rcu detected stall in neigh_periodic_work net 1 1 955d 955d 0/29 auto-obsoleted due to no activity on 2023/06/07 17:40
linux-6.1 INFO: rcu detected stall in neigh_periodic_work origin:upstream 1 syz 1 64d 137d 0/3 upstream: reported syz repro on 2025/06/04 08:32
▶ ▼ Last patch testing requests (1)
Created Duration User Patch Repo Result
2023/11/30 23:31 2h34m retest repro upstream report log
▶ ▼ Fix bisection attempts (3)
Created Duration User Patch Repo Result
2024/03/10 14:21 2h19m bisect fix upstream OK (0) job log log
2024/01/18 03:14 4h21m bisect fix upstream OK (0) job log log
2023/12/17 10:55 2h23m bisect fix upstream OK (0) job log log
marked invalid by web-security-scanner@google.com
▶ ▼ Cause bisection attempts (2)
Created Duration User Patch Repo Result
2024/01/12 15:00 12h50m bisect upstream error job log
2023/11/17 17:49 12h20m bisect upstream error job log
marked invalid by web-security-scanner@google.com

Sample crash report:
rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	1-...!: (640 ticks this GP) idle=716c/1/0x4000000000000000 softirq=6726/6726 fqs=0
rcu: 	(t=10502 jiffies g=6113 q=402 ncpus=2)
rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g6113 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=1 timer-softirq=21560
rcu: rcu_preempt kthread starved for 10502 jiffies! g6113 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:27904 pid:17    tgid:17    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5376 [inline]
 __schedule+0xedb/0x5af0 kernel/sched/core.c:6688
 __schedule_loop kernel/sched/core.c:6763 [inline]
 schedule+0xe9/0x270 kernel/sched/core.c:6778
 schedule_timeout+0x137/0x290 kernel/time/timer.c:2167
 rcu_gp_fqs_loop+0x1ec/0xb10 kernel/rcu/tree.c:1631
 rcu_gp_kthread+0x24b/0x380 kernel/rcu/tree.c:1830
 kthread+0x2c6/0x3a0 kernel/kthread.c:388
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 9 Comm: kworker/0:1 Not tainted 6.7.0-rc1-syzkaller-00125-g7475e51b8796 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023
Workqueue: events_power_efficient neigh_periodic_work
RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:27 [inline]
RIP: 0010:check_kcov_mode kernel/kcov.c:173 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0xd/0x60 kernel/kcov.c:207
Code: fa 48 8b be b0 01 00 00 e8 b0 ff ff ff 31 c0 c3 66 66 2e 0f 1f 84 00 00 00 00 00 66 90 f3 0f 1e fa 65 48 8b 14 25 c0 bc 03 00 <65> 8b 05 c4 2b 7c 7e a9 00 01 ff 00 48 8b 34 24 74 0f f6 c4 01 74
RSP: 0018:ffffc90000007e10 EFLAGS: 00000046
RAX: 0000000000010203 RBX: ffff8880b982ba40 RCX: ffffffff81764017
RDX: ffff888016660000 RSI: ffff8880b982ba40 RDI: ffff8880284b7340
RBP: ffff8880284b7340 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000003 R12: ffff8880b982b940
R13: 0000000000000000 R14: ffff8880284b7340 R15: 0000000000000001
FS:  0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f5b336df2d0 CR3: 000000000cd77000 CR4: 0000000000350ef0
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 debug_hrtimer_activate kernel/time/hrtimer.c:422 [inline]
 debug_activate kernel/time/hrtimer.c:477 [inline]
 enqueue_hrtimer+0x14/0x310 kernel/time/hrtimer.c:1087
 __run_hrtimer kernel/time/hrtimer.c:1705 [inline]
 __hrtimer_run_queues+0xa12/0xc20 kernel/time/hrtimer.c:1752
 hrtimer_interrupt+0x31b/0x800 kernel/time/hrtimer.c:1814
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1065 [inline]
 __sysvec_apic_timer_interrupt+0x105/0x400 arch/x86/kernel/apic/apic.c:1082
 sysvec_apic_timer_interrupt+0x90/0xb0 arch/x86/kernel/apic/apic.c:1076
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645
RIP: 0010:unwind_next_frame+0x15c/0x2390 arch/x86/kernel/unwind_orc.c:494
Code: 95 4d 00 4d 85 e4 0f 85 d9 02 00 00 e8 6d 99 4d 00 4c 8d 7b 35 48 b8 00 00 00 00 00 fc ff df 4c 89 fa 48 c1 ea 03 0f b6 04 02 <4c> 89 fa 83 e2 07 38 d0 7f 08 84 c0 0f 85 df 0b 00 00 48 b8 00 00
RSP: 0018:ffffc900000e76f0 EFLAGS: 00000213
RAX: 0000000000000000 RBX: ffffc900000e7770 RCX: 1ffffffff25010bc
RDX: 1ffff9200001cef4 RSI: ffffffff8139f783 RDI: 0000000000000001
RBP: 0000000000000001 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000003 R12: 0000000000000000
R13: ffffffff8174f8a0 R14: ffffc900000e7830 R15: ffffc900000e77a5
 arch_stack_walk+0xfa/0x170 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x96/0xd0 kernel/stacktrace.c:122
 kasan_save_stack+0x33/0x50 mm/kasan/common.c:45
 __kasan_record_aux_stack+0xbc/0xd0 mm/kasan/generic.c:492
 kvfree_call_rcu+0x70/0xbe0 kernel/rcu/tree.c:3400
 neigh_destroy+0x435/0x670 net/core/neighbour.c:911
 neigh_release include/net/neighbour.h:445 [inline]
 neigh_cleanup_and_release+0x1fe/0x290 net/core/neighbour.c:103
 neigh_periodic_work+0x6a7/0xc40 net/core/neighbour.c:998
 process_one_work+0x886/0x15d0 kernel/workqueue.c:2630
 process_scheduled_works kernel/workqueue.c:2703 [inline]
 worker_thread+0x8b9/0x1290 kernel/workqueue.c:2784
 kthread+0x2c6/0x3a0 kernel/kthread.c:388
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242
 </TASK>
INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.189 msecs
CPU: 1 PID: 5136 Comm: kworker/1:3 Not tainted 6.7.0-rc1-syzkaller-00125-g7475e51b8796 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023
Workqueue: ipv6_addrconf addrconf_dad_work
RIP: 0010:queued_write_lock_slowpath+0x179/0x330 kernel/locking/qrwlock.c:85
Code: 03 3d 00 01 00 00 74 37 48 b8 00 00 00 00 00 fc ff df 48 89 d9 48 89 da 48 c1 e9 03 83 e2 07 48 01 c1 83 c2 03 f3 90 0f b6 01 <38> c2 7c 08 84 c0 0f 85 5b 01 00 00 8b 03 3d 00 01 00 00 75 e6 48
RSP: 0018:ffffc900045ff560 EFLAGS: 00000206
RAX: 0000000000000000 RBX: ffffffff8ec890c0 RCX: fffffbfff1d91218
RDX: 0000000000000003 RSI: 0000000000000004 RDI: ffffffff8ec890c0
RBP: 1ffff920008bfeae R08: 0000000000000001 R09: fffffbfff1d91218
R10: ffffffff8ec890c3 R11: 0000000000000005 R12: ffffffff8ec890c4
R13: 0000000000000003 R14: fffffbfff1d91218 R15: ffffc900045ff5a0
FS:  0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055a99b6fb6d0 CR3: 000000007ecea000 CR4: 0000000000350ef0
Call Trace:
 <IRQ>
 </IRQ>
 <TASK>
 queued_write_lock include/asm-generic/qrwlock.h:101 [inline]
 do_raw_write_lock+0x1d2/0x3b0 kernel/locking/spinlock_debug.c:210
 ___neigh_create+0x9c2/0x2a20 net/core/neighbour.c:675
 ip6_finish_output2+0x10e9/0x1830 net/ipv6/ip6_output.c:128
 __ip6_finish_output net/ipv6/ip6_output.c:211 [inline]
 ip6_finish_output+0x3c7/0xf80 net/ipv6/ip6_output.c:222
 NF_HOOK_COND include/linux/netfilter.h:303 [inline]
 ip6_output+0x1e2/0x530 net/ipv6/ip6_output.c:243
 dst_output include/net/dst.h:451 [inline]
 NF_HOOK include/linux/netfilter.h:314 [inline]
 ndisc_send_skb+0xa13/0x18f0 net/ipv6/ndisc.c:509
 ndisc_send_rs+0x133/0x6a0 net/ipv6/ndisc.c:719
 addrconf_dad_completed+0x486/0x1030 net/ipv6/addrconf.c:4303
 addrconf_dad_work+0x7f6/0x14b0 net/ipv6/addrconf.c:4211
 process_one_work+0x886/0x15d0 kernel/workqueue.c:2630
 process_scheduled_works kernel/workqueue.c:2703 [inline]
 worker_thread+0x8b9/0x1290 kernel/workqueue.c:2784
 kthread+0x2c6/0x3a0 kernel/kthread.c:388
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242
 </TASK>

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/11/16 23:09 upstream 7475e51b8796 cb976f63 .config console log report syz C [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: rcu detected stall in neigh_periodic_work
2023/09/18 18:59 net-next a5ea26536e89 0b6a67ac .config console log report info ci-upstream-net-kasan-gce INFO: rcu detected stall in neigh_periodic_work
* Struck through repros no longer work on HEAD.