INFO: rcu detected stall in neigh_timer_handler (6)

Status: auto-closed as invalid on 2021/03/09 03:20
Subsystems: netfilter
[Documentation on labels]
First crash: 2055d, last: 2055d
▶ ▼ Similar bugs (16)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.6 INFO: rcu detected stall in neigh_timer_handler 1 1 144d 144d 0/2 auto-obsoleted due to no activity on 2026/06/12 03:02
upstream INFO: rcu detected stall in neigh_timer_handler (8) net 1 C done done 72 714d 773d 28/29 fixed on 2024/10/21 12:45
upstream INFO: rcu detected stall in neigh_timer_handler net 1 1 2801d 2801d 0/29 auto-closed as invalid on 2019/05/23 06:47
upstream INFO: rcu detected stall in neigh_timer_handler (2) net 1 2 2511d 2512d 13/29 fixed on 2019/10/09 10:54
upstream INFO: rcu detected stall in neigh_timer_handler (4) net 1 1 2426d 2426d 0/29 closed as invalid on 2019/12/04 14:04
linux-5.15 INFO: rcu detected stall in neigh_timer_handler 1 1 315d 315d 0/3 auto-obsoleted due to no activity on 2025/12/23 11:36
upstream INFO: rcu detected stall in neigh_timer_handler (5) net 1 1 2158d 2158d 0/29 auto-closed as invalid on 2020/11/26 10:25
linux-6.6 INFO: rcu detected stall in neigh_timer_handler (2) 1 1 1d02h 1d02h 0/2 upstream: reported on 2026/07/25 18:11
linux-5.15 INFO: rcu detected stall in neigh_timer_handler (2) 1 2 152d 153d 0/3 auto-obsoleted due to no activity on 2026/06/04 18:05
upstream INFO: rcu detected stall in neigh_timer_handler (3) net 1 2 2431d 2431d 0/29 closed as invalid on 2019/11/29 14:24
linux-6.1 INFO: rcu detected stall in neigh_timer_handler (3) 1 1 284d 284d 0/3 auto-obsoleted due to no activity on 2026/01/23 04:30
upstream INFO: rcu detected stall in neigh_timer_handler (7) net 1 1 1931d 1931d 0/29 auto-closed as invalid on 2021/07/11 19:14
linux-6.1 INFO: rcu detected stall in neigh_timer_handler (2) 1 1 538d 538d 0/3 auto-obsoleted due to no activity on 2025/05/14 07:23
linux-4.14 INFO: rcu detected stall in neigh_timer_handler 1 5 2276d 2395d 0/1 auto-closed as invalid on 2020/08/30 16:21
linux-6.1 INFO: rcu detected stall in neigh_timer_handler 1 4 669d 779d 0/3 auto-obsoleted due to no activity on 2025/01/03 05:12
upstream BUG: soft lockup in neigh_timer_handler (2) net 1 2 549d 579d 0/29 closed as invalid on 2025/02/28 15:46

Sample crash report:
rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	0-...!: (10472 ticks this GP) idle=2f2/1/0x4000000000000000 softirq=23016/23023 fqs=2 
	(t=10502 jiffies g=31429 q=237)
rcu: rcu_preempt kthread starved for 10499 jiffies! g31429 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:28880 pid:   11 ppid:     2 flags:0x00004000
Call Trace:
 context_switch kernel/sched/core.c:3779 [inline]
 __schedule+0x893/0x2130 kernel/sched/core.c:4528
 schedule+0xcf/0x270 kernel/sched/core.c:4606
 schedule_timeout+0x148/0x250 kernel/time/timer.c:1871
 rcu_gp_fqs_loop kernel/rcu/tree.c:1925 [inline]
 rcu_gp_kthread+0xb4c/0x1c90 kernel/rcu/tree.c:2099
 kthread+0x3b1/0x4a0 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296
NMI backtrace for cpu 0
CPU: 0 PID: 14611 Comm: syz-executor.5 Not tainted 5.10.0-rc7-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x107/0x163 lib/dump_stack.c:118
 nmi_cpu_backtrace.cold+0x44/0xd7 lib/nmi_backtrace.c:105
 nmi_trigger_cpumask_backtrace+0x1b3/0x230 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline]
 rcu_dump_cpu_stacks+0x1e3/0x21e kernel/rcu/tree_stall.h:331
 print_cpu_stall kernel/rcu/tree_stall.h:563 [inline]
 check_cpu_stall kernel/rcu/tree_stall.h:637 [inline]
 rcu_pending kernel/rcu/tree.c:3694 [inline]
 rcu_sched_clock_irq.cold+0x472/0xee8 kernel/rcu/tree.c:2567
 update_process_times+0x77/0xd0 kernel/time/timer.c:1709
 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:176
 tick_sched_timer+0x1d1/0x2a0 kernel/time/tick-sched.c:1328
 __run_hrtimer kernel/time/hrtimer.c:1519 [inline]
 __hrtimer_run_queues+0x1ce/0xea0 kernel/time/hrtimer.c:1583
 hrtimer_interrupt+0x334/0x940 kernel/time/hrtimer.c:1645
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1080 [inline]
 __sysvec_apic_timer_interrupt+0x146/0x540 arch/x86/kernel/apic/apic.c:1097
 run_sysvec_on_irqstack_cond arch/x86/include/asm/irq_stack.h:91 [inline]
 sysvec_apic_timer_interrupt+0x48/0x100 arch/x86/kernel/apic/apic.c:1091
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:631
RIP: 0010:apparmor_ipv6_postroute+0x2/0x1d0 include/linux/list.h:71
Code: 5d 83 05 20 8f 83 0b 01 41 5c e9 09 be 63 05 e8 14 57 2d fe eb 94 e8 0d 57 2d fe eb c7 48 89 df e8 03 57 2d fe eb 9f 90 41 54 <55> 53 48 89 f3 e8 04 d9 eb fd 48 8d bb a0 00 00 00 48 b8 00 00 00
RSP: 0018:ffffc90000007750 EFLAGS: 00000246
RAX: ffffffff83842b60 RBX: ffff888011c4e100 RCX: ffffffff872f47ed
RDX: ffffc90000007800 RSI: ffff88802a461640 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000001 R09: ffffffff8ebaf667
R10: 0000000000000000 R11: aa1414ac00000000 R12: ffff888011c4e100
R13: ffff88802a461640 R14: ffffc90000007800 R15: dffffc0000000000
 nf_hook_entry_hookfn include/linux/netfilter.h:136 [inline]
 nf_hook_slow+0xc5/0x1e0 net/netfilter/core.c:589
 nf_hook+0x3a1/0x670 include/linux/netfilter.h:256
 NF_HOOK_COND include/linux/netfilter.h:289 [inline]
 ip6_output+0x31e/0x520 net/ipv6/ip6_output.c:176
 dst_output include/net/dst.h:443 [inline]
 ip6_local_out+0xaf/0x1a0 net/ipv6/output_core.c:179
 ip6_send_skb+0xb7/0x340 net/ipv6/ip6_output.c:1865
 ip6_push_pending_frames+0xbd/0xe0 net/ipv6/ip6_output.c:1885
 icmpv6_push_pending_frames+0x294/0x470 net/ipv6/icmp.c:310
 icmp6_send+0x19df/0x2240 net/ipv6/icmp.c:626
 icmpv6_send include/linux/icmpv6.h:24 [inline]
 ip6_link_failure+0x29/0x510 net/ipv6/route.c:2669
 dst_link_failure include/net/dst.h:426 [inline]
 ndisc_error_report+0xc7/0x1c0 net/ipv6/ndisc.c:712
 neigh_invalidate+0x20d/0x560 net/core/neighbour.c:995
 neigh_timer_handler+0xd43/0x10e0 net/core/neighbour.c:1082
 call_timer_fn+0x1a5/0x6b0 kernel/time/timer.c:1410
 expire_timers kernel/time/timer.c:1455 [inline]
 __run_timers.part.0+0x67c/0xa50 kernel/time/timer.c:1747
 __run_timers kernel/time/timer.c:1728 [inline]
 run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1760
 __do_softirq+0x2a0/0x9f6 kernel/softirq.c:298
 asm_call_irq_on_stack+0xf/0x20
 </IRQ>
 __run_on_irqstack arch/x86/include/asm/irq_stack.h:26 [inline]
 run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:77 [inline]
 do_softirq_own_stack+0xaa/0xd0 arch/x86/kernel/irq_64.c:77
 invoke_softirq kernel/softirq.c:393 [inline]
 __irq_exit_rcu kernel/softirq.c:423 [inline]
 irq_exit_rcu+0x132/0x200 kernel/softirq.c:435
 sysvec_apic_timer_interrupt+0x4d/0x100 arch/x86/kernel/apic/apic.c:1091
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:631
RIP: 0010:lock_is_held_type+0xc2/0x100 kernel/locking/lockdep.c:5481
Code: 03 44 39 f0 41 0f 94 c4 48 c7 c7 40 5f 4b 89 e8 d4 0b 00 00 b8 ff ff ff ff 65 0f c1 05 67 78 1c 77 83 f8 01 75 23 ff 34 24 9d <48> 83 c4 08 44 89 e0 5b 5d 41 5c 41 5d 41 5e 41 5f c3 45 31 e4 eb
RSP: 0018:ffffc90001bffac0 EFLAGS: 00000202
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 1ffffffff19d9c03
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90000df3da0 R08: 0000000000000001 R09: ffff888074d11a63
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000001
R13: ffff888074d13d98 R14: 00000000ffffffff R15: ffff888074d13d98
 lock_is_held include/linux/lockdep.h:271 [inline]
 __unqueue_futex+0xf8/0x1b0 kernel/futex.c:1437
 mark_wake_futex+0x10f/0x1a0 kernel/futex.c:1458
 futex_wake+0x3b4/0x490 kernel/futex.c:1618
 do_futex+0x322/0x1a60 kernel/futex.c:3770
 __do_sys_futex+0x2a2/0x470 kernel/futex.c:3828
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45e0f9
Code: 0d b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 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 0f 83 db b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fe2a40c6cf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: ffffffffffffffda RBX: 000000000119bf88 RCX: 000000000045e0f9
RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 000000000119bf8c
RBP: 000000000119bf80 R08: 000000000000000e R09: 0000000000000000
R10: 0000000020ffc000 R11: 0000000000000246 R12: 000000000119bf8c
R13: 00007fff74d94e3f R14: 00007fe2a40c79c0 R15: 000000000119bf8c

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/12/09 03:12 upstream 7d8761ba27fc a7f7f4a4 .config console log report info ci-upstream-kasan-gce-root
* Struck through repros no longer work on HEAD.