INFO: rcu_sched detected stalls on CPUs/tasks: (detected by 1, t=120002 jiffies, g=74177, c=74176, q=65) All QSes seen, last rcu_sched kthread activity 120002 (4295110775-4294990773), jiffies_till_next_fqs=3, root ->qsmask 0x0 kworker/u4:3 R running task 55928 53 2 0x80000008 Workqueue: netns cleanup_net Call Trace: sched_show_task+0x610/0x740 kernel/sched/core.c:5346 print_other_cpu_stall kernel/rcu/tree.c:1481 [inline] check_cpu_stall kernel/rcu/tree.c:1599 [inline] __rcu_pending kernel/rcu/tree.c:3356 [inline] rcu_pending kernel/rcu/tree.c:3401 [inline] rcu_check_callbacks+0x277a/0x2ae0 kernel/rcu/tree.c:2763 update_process_times+0x132/0x1a0 kernel/time/timer.c:1636 tick_sched_handle kernel/time/tick-sched.c:164 [inline] tick_sched_timer+0x3ba/0x520 kernel/time/tick-sched.c:1274 __run_hrtimer kernel/time/hrtimer.c:1398 [inline] __hrtimer_run_queues+0xc54/0x1630 kernel/time/hrtimer.c:1460 hrtimer_interrupt+0x451/0x13c0 kernel/time/hrtimer.c:1518 local_apic_timer_interrupt+0x6b/0x250 arch/x86/kernel/apic/apic.c:1025 smp_apic_timer_interrupt+0x5a/0x90 arch/x86/kernel/apic/apic.c:1053 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:866 RIP: 0010:__read_once_size include/linux/compiler.h:197 [inline] RIP: 0010:csd_lock_wait kernel/smp.c:108 [inline] RIP: 0010:smp_call_function_single+0x35b/0x4e0 kernel/smp.c:302 RSP: 0018:ffff8801d862fa40 EFLAGS: 00000293 ORIG_RAX: ffffffffffffff13 RAX: ffffffff81539215 RBX: 0000000000000003 RCX: ffff8801d8be1d40 RDX: 0000000000000000 RSI: aaaaaaaaaaaab000 RDI: ffffea0000000000 RBP: ffff8801d862fb10 R08: 0000000000000000 R09: 0000000000000002 R10: 0000000000000000 R11: ffffffff81174e40 R12: ffff8801d862fab8 R13: 0000000000000000 R14: 0000000000000000 R15: ffff8801d8be2618 _rcu_barrier+0x497/0x760 kernel/rcu/tree.c:3544 rcu_barrier_sched kernel/rcu/tree.c:3584 [inline] rcu_barrier+0x1c/0x20 kernel/rcu/tree_plugin.h:898 cleanup_net+0x10ff/0x16b0 net/core/net_namespace.c:534 process_one_work+0x12e4/0x1fa0 kernel/workqueue.c:2145 worker_thread+0x113c/0x24f0 kernel/workqueue.c:2279 kthread+0x4db/0x6c0 kernel/kthread.c:241 ret_from_fork+0x35/0x40 arch/x86/entry/entry_64.S:413 rcu_sched kthread starved for 120002 jiffies! g74177 c74176 f0x2 RCU_GP_WAIT_FQS(3) ->state=0x0 ->cpu=0 RCU grace-period kthread stack dump: rcu_sched R running task 61960 9 2 0x80000000 Call Trace: context_switch kernel/sched/core.c:2880 [inline] __schedule+0x651/0x770 kernel/sched/core.c:3524 schedule+0x1cc/0x2f0 kernel/sched/core.c:3568 schedule_timeout+0x3ef/0x580 kernel/time/timer.c:1801 rcu_gp_kthread+0x21e1/0x38d0 kernel/rcu/tree.c:2231 kthread+0x4db/0x6c0 kernel/kthread.c:241 ret_from_fork+0x35/0x40 arch/x86/entry/entry_64.S:413