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INFO: rcu detected stall in linkwatch_event (3)

Status: closed as invalid on 2020/01/08 05:33
Subsystems: cgroups mm
[Documentation on labels]
First crash: 2056d, last: 2056d
▶ ▼ Similar bugs (4)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in linkwatch_event (5) net 1 syz error 1 65d 61d 0/29 upstream: reported syz repro on 2025/06/26 01:28
upstream INFO: rcu detected stall in linkwatch_event mm 1 252 2091d 2093d 0/29 closed as invalid on 2019/12/04 14:14
upstream INFO: rcu detected stall in linkwatch_event (2) mm 1 44 2056d 2057d 0/29 closed as invalid on 2020/01/08 05:23
upstream INFO: rcu detected stall in linkwatch_event (4) mm 1 67 2056d 2056d 0/29 closed as invalid on 2020/01/09 08:13

Sample crash report:
rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	0-...!: (1 GPs behind) idle=d62/1/0x4000000000000002 softirq=13948/13955 fqs=40 
	(t=10501 jiffies g=7029 q=89)
rcu: rcu_preempt kthread starved for 10422 jiffies! g7029 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
rcu: RCU grace-period kthread stack dump:
rcu_preempt     R  running task    29032    10      2 0x80004000
Call Trace:
 context_switch kernel/sched/core.c:3385 [inline]
 __schedule+0x9a0/0xcc0 kernel/sched/core.c:4081
 schedule+0x181/0x210 kernel/sched/core.c:4155
 schedule_timeout+0x14f/0x240 kernel/time/timer.c:1895
 rcu_gp_fqs_loop kernel/rcu/tree.c:1661 [inline]
 rcu_gp_kthread+0xed8/0x1770 kernel/rcu/tree.c:1821
 kthread+0x332/0x350 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
NMI backtrace for cpu 0
CPU: 0 PID: 3139 Comm: kworker/0:76 Not tainted 5.5.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events linkwatch_event
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1fb/0x318 lib/dump_stack.c:118
 nmi_cpu_backtrace+0xaf/0x1a0 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x174/0x290 lib/nmi_backtrace.c:62
 arch_trigger_cpumask_backtrace+0x10/0x20 arch/x86/kernel/apic/hw_nmi.c:38
 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline]
 rcu_dump_cpu_stacks+0x15a/0x220 kernel/rcu/tree_stall.h:254
 print_cpu_stall kernel/rcu/tree_stall.h:455 [inline]
 check_cpu_stall kernel/rcu/tree_stall.h:529 [inline]
 rcu_pending kernel/rcu/tree.c:2827 [inline]
 rcu_sched_clock_irq+0xe25/0x1ad0 kernel/rcu/tree.c:2271
 update_process_times+0x12d/0x180 kernel/time/timer.c:1726
 tick_sched_handle kernel/time/tick-sched.c:167 [inline]
 tick_sched_timer+0x263/0x420 kernel/time/tick-sched.c:1310
 __run_hrtimer kernel/time/hrtimer.c:1517 [inline]
 __hrtimer_run_queues+0x403/0x840 kernel/time/hrtimer.c:1579
 hrtimer_interrupt+0x38c/0xda0 kernel/time/hrtimer.c:1641
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1110 [inline]
 smp_apic_timer_interrupt+0x109/0x280 arch/x86/kernel/apic/apic.c:1135
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829
 </IRQ>
RIP: 0010:__memcg_kmem_uncharge+0x40/0x1a0 mm/memcontrol.c:2910
Code: 00 00 00 00 fc ff df 4c 8d 77 38 4d 89 f5 49 c1 ed 03 41 80 7c 05 00 00 74 08 4c 89 f7 e8 48 07 fb ff 4d 8b 3e b8 01 00 00 00 <89> d9 d3 e0 4d 85 ff 0f 84 de 00 00 00 4c 39 3d a4 be ac 07 0f 84
RSP: 0018:ffffc90008a5f6c0 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000001 RBX: 0000000000000000 RCX: ffff88809dd3e4c0
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffea00022f6c80
RBP: ffffc90008a5f6f0 R08: dffffc0000000000 R09: fffffbfff124248a
R10: fffffbfff124248a R11: 0000000000000000 R12: ffffea00022f6c80
R13: 1ffffd400045ed97 R14: ffffea00022f6cb8 R15: 0000000000000000
 memcg_kmem_uncharge include/linux/memcontrol.h:1402 [inline]
 free_thread_stack+0x12e/0x590 kernel/fork.c:284
 release_task_stack kernel/fork.c:440 [inline]
 put_task_stack+0xa3/0x130 kernel/fork.c:451
 finish_task_switch+0x3f1/0x550 kernel/sched/core.c:3256
 context_switch kernel/sched/core.c:3388 [inline]
 __schedule+0x9a8/0xcc0 kernel/sched/core.c:4081
 preempt_schedule_common kernel/sched/core.c:4236 [inline]
 preempt_schedule+0xdb/0x120 kernel/sched/core.c:4261
 ___preempt_schedule+0x16/0x18 arch/x86/entry/thunk_64.S:50
 vprintk_emit+0x36d/0x3a0 kernel/printk/printk.c:1997
 vprintk_default+0x28/0x30 kernel/printk/printk.c:2023
 vprintk_func+0x158/0x170 kernel/printk/printk_safe.c:386
 printk+0x62/0x8d kernel/printk/printk.c:2056
 addrconf_notify+0x2c8d/0x3c90 net/ipv6/addrconf.c:3573
 notifier_call_chain kernel/notifier.c:83 [inline]
 __raw_notifier_call_chain kernel/notifier.c:361 [inline]
 raw_notifier_call_chain+0xec/0x190 kernel/notifier.c:368
 call_netdevice_notifiers_info net/core/dev.c:1893 [inline]
 netdev_state_change+0x147/0x1f0 net/core/dev.c:1378
 linkwatch_do_dev+0x10e/0x160 net/core/link_watch.c:159
 __linkwatch_run_queue+0x446/0x730 net/core/link_watch.c:204
 linkwatch_event+0x4c/0x60 net/core/link_watch.c:243
 process_one_work+0x7ef/0x10d0 kernel/workqueue.c:2264
 worker_thread+0xc01/0x1630 kernel/workqueue.c:2410
 kthread+0x332/0x350 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/01/08 05:26 upstream ae6088216ce4 6738e0b3 .config console log report ci-upstream-kasan-gce-smack-root
* Struck through repros no longer work on HEAD.