rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 1-...!: (10500 ticks this GP) idle=6a2/1/0x4000000000000004 softirq=90457/90457 fqs=0 rcu: (t=10500 jiffies g=110037 q=4351) rcu: rcu_preempt kthread starved for 10500 jiffies! g110037 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=1 rcu: RCU grace-period kthread stack dump: rcu_preempt I29104 10 2 0x80000000 Call Trace: context_switch kernel/sched/core.c:2826 [inline] __schedule+0x866/0x1dc0 kernel/sched/core.c:3474 schedule+0x92/0x1c0 kernel/sched/core.c:3518 schedule_timeout+0x4db/0xfc0 kernel/time/timer.c:1804 rcu_gp_kthread+0xd5c/0x2190 kernel/rcu/tree.c:2202 kthread+0x354/0x420 kernel/kthread.c:246 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 NMI backtrace for cpu 1 CPU: 1 PID: 7606 Comm: kworker/u4:5 Not tainted 4.19.72 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: netns cleanup_net Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x172/0x1f0 lib/dump_stack.c:113 nmi_cpu_backtrace.cold+0x63/0xa4 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1b0/0x1f8 lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline] rcu_dump_cpu_stacks+0x189/0x1d5 kernel/rcu/tree.c:1340 print_cpu_stall kernel/rcu/tree.c:1478 [inline] check_cpu_stall kernel/rcu/tree.c:1550 [inline] __rcu_pending kernel/rcu/tree.c:3293 [inline] rcu_pending kernel/rcu/tree.c:3336 [inline] rcu_check_callbacks.cold+0x5e3/0xd90 kernel/rcu/tree.c:2682 update_process_times+0x32/0x80 kernel/time/timer.c:1636 tick_sched_handle+0xa2/0x190 kernel/time/tick-sched.c:164 tick_sched_timer+0x47/0x130 kernel/time/tick-sched.c:1274 __run_hrtimer kernel/time/hrtimer.c:1398 [inline] __hrtimer_run_queues+0x33b/0xdc0 kernel/time/hrtimer.c:1460 hrtimer_interrupt+0x314/0x770 kernel/time/hrtimer.c:1518 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1067 [inline] smp_apic_timer_interrupt+0x111/0x550 arch/x86/kernel/apic/apic.c:1092 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:893 RIP: 0010:get_current arch/x86/include/asm/current.h:15 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x8/0x50 kernel/kcov.c:100 Code: 66 ea ff 48 c7 05 44 22 cd 08 00 00 00 00 e9 ca e9 ff ff 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 55 48 89 e5 48 8b 75 08 <65> 48 8b 04 25 40 ee 01 00 65 8b 15 28 97 96 7e 81 e2 00 01 1f 00 RSP: 0018:ffff8880ae9074c8 EFLAGS: 00000202 ORIG_RAX: ffffffffffffff13 RAX: 0000000000000501 RBX: ffff8880a9a69938 RCX: ffffffff858e7e8e RDX: 0000000000000001 RSI: ffffffff858e7ea0 RDI: 0000000000000001 RBP: ffff8880ae9074c8 R08: ffff88805865c040 R09: 0000000000000008 R10: ffff88805865ca00 R11: 00000000b9253308 R12: dffffc0000000000 R13: ffff8880a9a69680 R14: ffff8880a9a699d8 R15: ffff8880a9a699d0 __list_add include/linux/list.h:63 [inline] list_add_tail include/linux/list.h:93 [inline] list_move_tail include/linux/list.h:183 [inline] hhf_dequeue+0x670/0xa00 net/sched/sch_hhf.c:438 dequeue_skb net/sched/sch_generic.c:277 [inline] qdisc_restart net/sched/sch_generic.c:380 [inline] __qdisc_run+0x1e7/0x1960 net/sched/sch_generic.c:398 __dev_xmit_skb net/core/dev.c:3501 [inline] __dev_queue_xmit+0x165c/0x2fe0 net/core/dev.c:3811 dev_queue_xmit+0x18/0x20 net/core/dev.c:3876 neigh_resolve_output net/core/neighbour.c:1369 [inline] neigh_resolve_output+0x5b7/0x980 net/core/neighbour.c:1349 neigh_output include/net/neighbour.h:501 [inline] ip6_finish_output2+0xb7f/0x2550 net/ipv6/ip6_output.c:120 ip6_finish_output+0x574/0xbe0 net/ipv6/ip6_output.c:154 NF_HOOK_COND include/linux/netfilter.h:278 [inline] ip6_output+0x235/0x7c0 net/ipv6/ip6_output.c:171 dst_output include/net/dst.h:447 [inline] NF_HOOK include/linux/netfilter.h:289 [inline] ndisc_send_skb+0xf3b/0x1460 net/ipv6/ndisc.c:491 ndisc_send_rs+0x134/0x6d0 net/ipv6/ndisc.c:685 addrconf_rs_timer+0x30f/0x680 net/ipv6/addrconf.c:3821 call_timer_fn+0x18d/0x720 kernel/time/timer.c:1326 expire_timers kernel/time/timer.c:1363 [inline] __run_timers kernel/time/timer.c:1682 [inline] __run_timers kernel/time/timer.c:1650 [inline] run_timer_softirq+0x652/0x1700 kernel/time/timer.c:1695 __do_softirq+0x25c/0x921 kernel/softirq.c:292 invoke_softirq kernel/softirq.c:372 [inline] irq_exit+0x180/0x1d0 kernel/softirq.c:412 exiting_irq arch/x86/include/asm/apic.h:536 [inline] smp_apic_timer_interrupt+0x13b/0x550 arch/x86/kernel/apic/apic.c:1094 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:893 RIP: 0010:__rcu_read_lock+0x2a/0x50 kernel/rcu/tree_plugin.h:405 Code: 48 b8 00 00 00 00 00 fc ff df 55 48 89 e5 53 65 48 8b 1c 25 40 ee 01 00 48 8d bb 70 03 00 00 48 89 fa 48 c1 ea 03 0f b6 04 02 <84> c0 74 04 3c 03 7e 0a 83 83 70 03 00 00 01 5b 5d c3 e8 9f 07 49 RSP: 0018:ffff88805866fb70 EFLAGS: 00000a02 ORIG_RAX: ffffffffffffff13 RAX: 0000000000000000 RBX: ffff88805865c040 RCX: ffff88805865c8c0 RDX: 1ffff1100b0cb876 RSI: ffffffff8879f2a0 RDI: ffff88805865c3b0 RBP: ffff88805866fb78 R08: ffff88805865c040 R09: 0000000000000003 R10: ffffed1015d24732 R11: ffff8880ae923993 R12: 000000000000000a R13: 0000000000000001 R14: 000000000001d0eb R15: dffffc0000000000 rcu_read_lock include/linux/rcupdate.h:625 [inline] inet_twsk_purge+0x9b/0x5e8 net/ipv4/inet_timewait_sock.c:267 dccp_v6_exit_batch+0x1a/0x20 net/dccp/ipv6.c:1113 ops_exit_list.isra.0+0xfc/0x150 net/core/net_namespace.c:156 cleanup_net+0x3fb/0x960 net/core/net_namespace.c:552 process_one_work+0x989/0x1750 kernel/workqueue.c:2153 worker_thread+0x98/0xe40 kernel/workqueue.c:2296 kthread+0x354/0x420 kernel/kthread.c:246 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415