INFO: rcu detected stall in linkwatch

Kernel	Title	Count	Last	Reported	Patched	Status
upstream	INFO: rcu detected stall in linkwatch_event kernel	252	1939d	1940d	0/28	closed as invalid on 2019/12/04 14:14
upstream	INFO: rcu detected stall in linkwatch_event (2) kernel	44	1904d	1904d	0/28	closed as invalid on 2020/01/08 05:23
upstream	INFO: rcu detected stall in linkwatch_event (4) kernel	67	1904d	1904d	0/28	closed as invalid on 2020/01/09 08:13

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