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INFO: rcu detected stall in neigh_periodic_work

Status: auto-obsoleted due to no activity on 2023/06/07 17:40
Subsystems: net
[Documentation on labels]
First crash: 918d, last: 918d
▶ ▼ 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 (2) net 1 C error 2 551d 723d 0/29 closed as invalid on 2024/03/13 18:06
upstream INFO: rcu detected stall in neigh_periodic_work (4) net 1 1 133d 133d 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 254d 287d 0/29 closed as invalid on 2025/01/28 16:26
upstream INFO: rcu detected stall in neigh_periodic_work (3) net 1 2 489d 508d 0/29 auto-obsoleted due to no activity on 2024/08/09 21:19
linux-6.1 INFO: rcu detected stall in neigh_periodic_work origin:upstream 1 syz 1 28d 101d 0/3 upstream: reported syz repro on 2025/06/04 08:32

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (1 GPs behind) idle=2c74/1/0x4000000000000000 softirq=96093/96094 fqs=735
rcu: 	(detected by 1, t=10502 jiffies, g=158645, q=1107 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 5180 Comm: kworker/0:6 Not tainted 6.2.0-syzkaller-12970-ged69e0667db5 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/02/2023
Workqueue: events_power_efficient neigh_periodic_work
RIP: 0010:__lock_acquire+0xb61/0x5d40 kernel/locking/lockdep.c:5051
Code: fc ff df 48 c1 ea 03 0f b6 14 02 48 c7 c0 ec 9e 78 8e 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 72 3d 00 00 8b 15 bb a6 12 0d <85> d2 0f 85 a3 00 00 00 8b 44 24 18 85 c0 0f 85 28 0b 00 00 48 b8
RSP: 0018:ffffc90000007bb8 EFLAGS: 00000046
RAX: 0000000000000007 RBX: 0000000000000040 RCX: ffffffff8165fb89
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffff888026638ad1
RBP: ffff888026638ad2 R08: 0000000000000000 R09: ffffffff914e0b8f
R10: fffffbfff229c171 R11: 0000000000000000 R12: ffff888026638ab0
R13: ffff888026638000 R14: 0000000000000001 R15: fad1fefc6e50c6aa
FS:  0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa0ac70e262 CR3: 000000000c571000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 lock_acquire kernel/locking/lockdep.c:5669 [inline]
 lock_acquire+0x1e3/0x670 kernel/locking/lockdep.c:5634
 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:119 [inline]
 _raw_spin_lock_irq+0x36/0x50 kernel/locking/spinlock.c:170
 __run_hrtimer kernel/time/hrtimer.c:1689 [inline]
 __hrtimer_run_queues+0x266/0x1010 kernel/time/hrtimer.c:1749
 hrtimer_interrupt+0x320/0x7b0 kernel/time/hrtimer.c:1811
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1096 [inline]
 __sysvec_apic_timer_interrupt+0x180/0x660 arch/x86/kernel/apic/apic.c:1113
 sysvec_apic_timer_interrupt+0x92/0xc0 arch/x86/kernel/apic/apic.c:1107
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645
RIP: 0010:__raw_read_unlock_irqrestore include/linux/rwlock_api_smp.h:242 [inline]
RIP: 0010:_raw_read_unlock_irqrestore+0x3c/0x70 kernel/locking/spinlock.c:268
Code: 74 24 10 e8 56 8b 4a f7 48 89 ef e8 4e 00 4b f7 81 e3 00 02 00 00 75 25 9c 58 f6 c4 02 75 2d 48 85 db 74 01 fb bf 01 00 00 00 <e8> 5f d1 3c f7 65 8b 05 30 ee e7 75 85 c0 74 0a 5b 5d c3 e8 2c cc
RSP: 0018:ffffc90004bffb38 EFLAGS: 00000206
RAX: 0000000000000016 RBX: 0000000000000200 RCX: 1ffffffff229f19e
RDX: 0000000000000000 RSI: 0000000000000202 RDI: 0000000000000001
RBP: ffffffff8e194e80 R08: 0000000000000001 R09: ffffffff914e0bbf
R10: 0000000000000001 R11: 0000000000094001 R12: 0000000000000293
R13: ffff8880751b4000 R14: ffff8880751b4000 R15: 0000000000000000
 netlink_lock_table net/netlink/af_netlink.c:474 [inline]
 netlink_broadcast+0x9e/0xd90 net/netlink/af_netlink.c:1533
 nlmsg_multicast include/net/netlink.h:1083 [inline]
 nlmsg_notify+0x93/0x280 net/netlink/af_netlink.c:2617
 __neigh_notify+0xdc/0x160 net/core/neighbour.c:3544
 neigh_cleanup_and_release+0xc3/0x3f0 net/core/neighbour.c:101
 neigh_periodic_work+0x60c/0xac0 net/core/neighbour.c:1025
 process_one_work+0x9bf/0x1820 kernel/workqueue.c:2390
 worker_thread+0x669/0x1090 kernel/workqueue.c:2537
 kthread+0x2e8/0x3a0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 9004 jiffies! g158645 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=1 timer-softirq=81333
rcu: rcu_preempt kthread starved for 9005 jiffies! g158645 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:28672 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5304 [inline]
 __schedule+0xcce/0x5b20 kernel/sched/core.c:6622
 schedule+0xde/0x1a0 kernel/sched/core.c:6698
 schedule_timeout+0x14e/0x2b0 kernel/time/timer.c:2167
 rcu_gp_fqs_loop+0x190/0x910 kernel/rcu/tree.c:1608
 rcu_gp_kthread+0x23a/0x360 kernel/rcu/tree.c:1807
 kthread+0x2e8/0x3a0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 PID: 5079 Comm: syz-fuzzer Not tainted 6.2.0-syzkaller-12970-ged69e0667db5 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/02/2023
RIP: 0010:queued_write_lock_slowpath+0x14b/0x2c9 kernel/locking/qrwlock.c:85
Code: ff df 49 01 c7 41 83 c6 03 41 0f b6 07 41 38 c6 7c 08 84 c0 0f 85 46 01 00 00 8b 45 00 3d 00 01 00 00 74 19 f3 90 41 0f b6 07 <41> 38 c6 7c eb 84 c0 74 e7 48 89 ef e8 84 d1 ba f7 eb dd 48 89 ef
RSP: 0000:ffffc90003ddf680 EFLAGS: 00000206
RAX: 0000000000000000 RBX: 1ffff920007bbed1 RCX: ffffffff8a1be78d
RDX: fffffbfff1c571e1 RSI: 0000000000000004 RDI: ffffffff8e2b8f00
RBP: ffffffff8e2b8f00 R08: 0000000000000001 R09: ffffffff8e2b8f03
R10: fffffbfff1c571e0 R11: 0000000000000001 R12: ffffffff8e2b8f04
R13: 00000000000000ff R14: 0000000000000003 R15: fffffbfff1c571e0
FS:  000000c000bb4490(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000c0054a7f90 CR3: 000000007a5c7000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 queued_write_lock include/asm-generic/qrwlock.h:101 [inline]
 do_raw_write_lock+0x1d2/0x3b0 kernel/locking/spinlock_debug.c:210
 neigh_forced_gc net/core/neighbour.c:261 [inline]
 neigh_alloc net/core/neighbour.c:476 [inline]
 ___neigh_create+0x11ff/0x2ba0 net/core/neighbour.c:671
 ip6_finish_output2+0x1000/0x1590 net/ipv6/ip6_output.c:125
 __ip6_finish_output net/ipv6/ip6_output.c:195 [inline]
 ip6_finish_output+0x694/0x1170 net/ipv6/ip6_output.c:206
 NF_HOOK_COND include/linux/netfilter.h:291 [inline]
 ip6_output+0x1f1/0x540 net/ipv6/ip6_output.c:227
 dst_output include/net/dst.h:444 [inline]
 NF_HOOK include/linux/netfilter.h:302 [inline]
 ndisc_send_skb+0xa63/0x1850 net/ipv6/ndisc.c:508
 ndisc_send_rs+0x132/0x6f0 net/ipv6/ndisc.c:718
 addrconf_rs_timer+0x3f1/0x870 net/ipv6/addrconf.c:3936
 call_timer_fn+0x1da/0x800 kernel/time/timer.c:1700
 expire_timers+0x2c6/0x5e0 kernel/time/timer.c:1751
 __run_timers kernel/time/timer.c:2022 [inline]
 __run_timers kernel/time/timer.c:1995 [inline]
 run_timer_softirq+0x326/0x910 kernel/time/timer.c:2035
 __do_softirq+0x2e3/0xae3 kernel/softirq.c:571
 invoke_softirq kernel/softirq.c:445 [inline]
 __irq_exit_rcu+0x114/0x190 kernel/softirq.c:650
 irq_exit_rcu+0x9/0x20 kernel/softirq.c:662
 sysvec_apic_timer_interrupt+0x49/0xc0 arch/x86/kernel/apic/apic.c:1107
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645
RIP: 0033:0x41f685
Code: ce 77 a6 4c 89 44 24 70 48 89 7c 24 50 48 89 4c 24 60 48 89 5c 24 58 48 89 44 24 68 4c 89 d0 48 89 d3 4c 89 c1 e8 3b 53 ff ff <48> 85 c0 74 1d 48 89 df 48 8b b4 24 98 00 00 00 49 89 c8 48 8b 5c
RSP: 002b:000000c000067e88 EFLAGS: 00000202
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: deaddeaddeaddead RDI: 000000000000000a
RBP: 000000c000067f08 R08: 0000000000000000 R09: ffffff3ffc420500
R10: 00000000018c7c20 R11: 0000000000000084 R12: 000000c000067f08
R13: 0000000000000000 R14: 000000c0003f91e0 R15: 0000000000000004
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/03/09 17:32 net-next ed69e0667db5 f08b59ac .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.