rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: (detected by 0, t=10502 jiffies, g=6685, q=45) rcu: All QSes seen, last rcu_preempt kthread activity 10503 (4294974859-4294964356), jiffies_till_next_fqs=1, root ->qsmask 0x0 kworker/0:1 R running task 26728 12 2 0x80004008 Workqueue: events iterate_cleanup_work Call Trace: sched_show_task kernel/sched/core.c:5833 [inline] sched_show_task.cold+0x2ed/0x34e kernel/sched/core.c:5808 print_other_cpu_stall kernel/rcu/tree_stall.h:410 [inline] check_cpu_stall kernel/rcu/tree_stall.h:538 [inline] rcu_pending kernel/rcu/tree.c:2795 [inline] rcu_sched_clock_irq.cold+0xafc/0xc12 kernel/rcu/tree.c:2244 update_process_times+0x2d/0x70 kernel/time/timer.c:1724 tick_sched_handle+0xa2/0x190 kernel/time/tick-sched.c:167 tick_sched_timer+0x53/0x140 kernel/time/tick-sched.c:1299 __run_hrtimer kernel/time/hrtimer.c:1504 [inline] __hrtimer_run_queues+0x364/0xe40 kernel/time/hrtimer.c:1566 hrtimer_interrupt+0x314/0x770 kernel/time/hrtimer.c:1628 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1106 [inline] smp_apic_timer_interrupt+0x160/0x610 arch/x86/kernel/apic/apic.c:1131 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:830 RIP: 0010:cpu_relax arch/x86/include/asm/processor.h:656 [inline] RIP: 0010:virt_spin_lock arch/x86/include/asm/qspinlock.h:99 [inline] RIP: 0010:native_queued_spin_lock_slowpath+0x132/0x9f0 kernel/locking/qspinlock.c:325 Code: 00 00 00 48 8b 45 d0 65 48 33 04 25 28 00 00 00 0f 85 37 07 00 00 48 81 c4 98 00 00 00 5b 41 5c 41 5d 41 5e 41 5f 5d c3 f3 90 73 ff ff ff 8b 45 98 4c 8d 65 d8 3d 00 01 00 00 0f 84 e5 00 00 RSP: 0018:ffff8880ae808fa0 EFLAGS: 00000202 ORIG_RAX: ffffffffffffff13 RAX: 0000000000000000 RBX: ffff8880a1e8f8e8 RCX: ffffffff815924c7 RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff8880a1e8f8e8 RBP: ffff8880ae809060 R08: 1ffff110143d1f1d R09: ffffed10143d1f1e R10: ffffed10143d1f1d R11: ffff8880a1e8f8eb R12: 0000000000000001 R13: 0000000000000003 R14: ffffed10143d1f1d R15: 0000000000000001 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:642 [inline] queued_spin_lock_slowpath arch/x86/include/asm/qspinlock.h:50 [inline] queued_spin_lock include/asm-generic/qspinlock.h:81 [inline] do_raw_spin_lock+0x20e/0x2e0 kernel/locking/spinlock_debug.c:113 __raw_spin_lock include/linux/spinlock_api_smp.h:143 [inline] _raw_spin_lock+0x37/0x40 kernel/locking/spinlock.c:151 spin_lock include/linux/spinlock.h:338 [inline] __dev_xmit_skb net/core/dev.c:3502 [inline] __dev_queue_xmit+0x14b8/0x37c0 net/core/dev.c:3838 dev_queue_xmit+0x18/0x20 net/core/dev.c:3902 br_dev_queue_push_xmit+0x3f3/0x5e0 net/bridge/br_forward.c:52 NF_HOOK include/linux/netfilter.h:305 [inline] NF_HOOK include/linux/netfilter.h:299 [inline] br_forward_finish+0xfa/0x400 net/bridge/br_forward.c:65 NF_HOOK include/linux/netfilter.h:305 [inline] NF_HOOK include/linux/netfilter.h:299 [inline] __br_forward+0x641/0xb00 net/bridge/br_forward.c:109 deliver_clone+0x61/0xc0 net/bridge/br_forward.c:125 maybe_deliver+0x2c7/0x390 net/bridge/br_forward.c:181 br_flood+0x13a/0x3d0 net/bridge/br_forward.c:223 br_dev_xmit+0x98c/0x15a0 net/bridge/br_device.c:100 __netdev_start_xmit include/linux/netdevice.h:4419 [inline] netdev_start_xmit include/linux/netdevice.h:4433 [inline] xmit_one net/core/dev.c:3280 [inline] dev_hard_start_xmit+0x1a3/0x9c0 net/core/dev.c:3296 __dev_queue_xmit+0x2b82/0x37c0 net/core/dev.c:3869 dev_queue_xmit+0x18/0x20 net/core/dev.c:3902 neigh_hh_output include/net/neighbour.h:500 [inline] neigh_output include/net/neighbour.h:509 [inline] ip_finish_output2+0x1752/0x2590 net/ipv4/ip_output.c:228 __ip_finish_output net/ipv4/ip_output.c:308 [inline] __ip_finish_output+0x5fc/0xbc0 net/ipv4/ip_output.c:290 ip_finish_output+0x38/0x1f0 net/ipv4/ip_output.c:318 NF_HOOK_COND include/linux/netfilter.h:294 [inline] ip_output+0x21f/0x670 net/ipv4/ip_output.c:432 dst_output include/net/dst.h:436 [inline] ip_local_out+0xbb/0x1b0 net/ipv4/ip_output.c:125 igmpv3_sendpack+0x1b5/0x2e0 net/ipv4/igmp.c:426 igmpv3_send_cr net/ipv4/igmp.c:721 [inline] igmp_ifc_timer_expire+0x687/0xa00 net/ipv4/igmp.c:809 call_timer_fn+0x1ac/0x780 kernel/time/timer.c:1404 expire_timers kernel/time/timer.c:1449 [inline] __run_timers kernel/time/timer.c:1771 [inline] __run_timers kernel/time/timer.c:1738 [inline] run_timer_softirq+0x6c0/0x17f0 kernel/time/timer.c:1784 __do_softirq+0x262/0x98c kernel/softirq.c:292 invoke_softirq kernel/softirq.c:373 [inline] irq_exit+0x19b/0x1e0 kernel/softirq.c:413 exiting_irq arch/x86/include/asm/apic.h:536 [inline] smp_apic_timer_interrupt+0x1a3/0x610 arch/x86/kernel/apic/apic.c:1133 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:830 RIP: 0010:should_resched arch/x86/include/asm/preempt.h:102 [inline] RIP: 0010:__local_bh_enable_ip+0x18e/0x270 kernel/softirq.c:196 Code: 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 0f 85 df 00 00 00 48 83 3d ff ac ad 07 00 0f 84 8f 00 00 00 fb 66 0f 1f 44 00 00 <65> 8b 05 43 bd bc 7e 85 c0 74 7f 5b 41 5c 41 5d 5d c3 80 3d ef 58 RSP: 0018:ffff8880a98cfbb0 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13 RAX: 1ffffffff11e5db6 RBX: 0000000000000200 RCX: 0000000000000006 RDX: dffffc0000000000 RSI: 0000000000000008 RDI: ffff8880a98bcb9c RBP: ffff8880a98cfbc8 R08: 1ffffffff14ed342 R09: fffffbfff14ed343 R10: fffffbfff14ed342 R11: ffffffff8a769a17 R12: ffffffff85d70311 R13: ffff8880a98bc300 R14: 0000000000000001 R15: dffffc0000000000 local_bh_enable include/linux/bottom_half.h:32 [inline] get_next_corpse net/netfilter/nf_conntrack_core.c:2014 [inline] nf_ct_iterate_cleanup+0x217/0x4e0 net/netfilter/nf_conntrack_core.c:2037 nf_ct_iterate_cleanup_net net/netfilter/nf_conntrack_core.c:2122 [inline] nf_ct_iterate_cleanup_net+0x133/0x190 net/netfilter/nf_conntrack_core.c:2107 iterate_cleanup_work+0x4a/0xd7 net/netfilter/nf_nat_masquerade.c:216 process_one_work+0x9af/0x1740 kernel/workqueue.c:2269 worker_thread+0x98/0xe40 kernel/workqueue.c:2415 kthread+0x361/0x430 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 rcu: rcu_preempt kthread starved for 10582 jiffies! g6685 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1 rcu: RCU grace-period kthread stack dump: rcu_preempt R running task 29360 10 2 0x80004000 Call Trace: context_switch kernel/sched/core.c:3265 [inline] __schedule+0x76e/0x17a0 kernel/sched/core.c:3937 schedule+0xd9/0x260 kernel/sched/core.c:4004 schedule_timeout+0x486/0xc50 kernel/time/timer.c:1893 rcu_gp_fqs_loop kernel/rcu/tree.c:1639 [inline] rcu_gp_kthread+0x9b2/0x18d0 kernel/rcu/tree.c:1799 kthread+0x361/0x430 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352