rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 1-...!: (1 GPs behind) idle=efa/1/0x4000000000000002 softirq=11109/11110 fqs=8 (t=10500 jiffies g=10437 q=43) rcu: rcu_preempt kthread starved for 10484 jiffies! g10437 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=0 rcu: RCU grace-period kthread stack dump: rcu_preempt I29688 10 2 0x80004000 Call Trace: context_switch kernel/sched/core.c:3254 [inline] __schedule+0x755/0x1580 kernel/sched/core.c:3880 schedule+0xd9/0x260 kernel/sched/core.c:3947 schedule_timeout+0x486/0xc50 kernel/time/timer.c:1807 rcu_gp_fqs_loop kernel/rcu/tree.c:1611 [inline] rcu_gp_kthread+0x9b2/0x18c0 kernel/rcu/tree.c:1768 kthread+0x361/0x430 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 NMI backtrace for cpu 1 CPU: 1 PID: 16 Comm: ksoftirqd/1 Not tainted 5.3.0-rc8+ #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x172/0x1f0 lib/dump_stack.c:113 nmi_cpu_backtrace.cold+0x70/0xb2 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x23b/0x28b 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+0x183/0x1cf 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:2736 [inline] rcu_sched_clock_irq.cold+0x4dd/0xc13 kernel/rcu/tree.c:2183 update_process_times+0x32/0x80 kernel/time/timer.c:1639 tick_sched_handle+0xa2/0x190 kernel/time/tick-sched.c:167 tick_sched_timer+0x53/0x140 kernel/time/tick-sched.c:1296 __run_hrtimer kernel/time/hrtimer.c:1389 [inline] __hrtimer_run_queues+0x364/0xe40 kernel/time/hrtimer.c:1451 hrtimer_interrupt+0x314/0x770 kernel/time/hrtimer.c:1509 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:hhf_dequeue+0xaf/0xa20 net/sched/sch_hhf.c:434 Code: 00 0f 85 6d 07 00 00 49 8b 1e 48 8d 7b 10 48 89 f8 48 c1 e8 03 42 0f b6 04 20 84 c0 74 08 3c 03 0f 8e 69 07 00 00 44 8b 7b 10 <31> ff 44 89 fe e8 37 1b ac fb 45 85 ff 0f 8e 70 04 00 00 e8 a9 19 RSP: 0018:ffff8880a99169a8 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 RAX: 0000000000000000 RBX: ffff8880a226b0b8 RCX: ffffffff85c660f9 RDX: 0000000000000100 RSI: ffffffff85c65afa RDI: ffff8880a226b0c8 RBP: ffff8880a99169f8 R08: ffff8880a990a440 R09: 0000000000000000 R10: fffffbfff134afaf R11: ffff8880a990a440 R12: dffffc0000000000 R13: ffff8880a226adc0 R14: ffff8880a226b150 R15: 0000000000000000 dequeue_skb net/sched/sch_generic.c:258 [inline] qdisc_restart net/sched/sch_generic.c:361 [inline] __qdisc_run+0x1e7/0x19d0 net/sched/sch_generic.c:379 __dev_xmit_skb net/core/dev.c:3533 [inline] __dev_queue_xmit+0x16f1/0x3650 net/core/dev.c:3838 dev_queue_xmit+0x18/0x20 net/core/dev.c:3902 br_dev_queue_push_xmit+0x3f3/0x5c0 net/bridge/br_forward.c:52 br_nf_dev_queue_xmit+0x34e/0x1470 net/bridge/br_netfilter_hooks.c:796 NF_HOOK include/linux/netfilter.h:305 [inline] NF_HOOK include/linux/netfilter.h:299 [inline] br_nf_post_routing+0x1502/0x1d30 net/bridge/br_netfilter_hooks.c:844 nf_hook_entry_hookfn include/linux/netfilter.h:135 [inline] nf_hook_slow+0xbc/0x1e0 net/netfilter/core.c:512 nf_hook include/linux/netfilter.h:260 [inline] NF_HOOK include/linux/netfilter.h:303 [inline] br_forward_finish+0x215/0x400 net/bridge/br_forward.c:65 br_nf_hook_thresh+0x2e9/0x370 net/bridge/br_netfilter_hooks.c:1015 br_nf_forward_finish+0x66c/0xa90 net/bridge/br_netfilter_hooks.c:560 NF_HOOK include/linux/netfilter.h:305 [inline] NF_HOOK include/linux/netfilter.h:299 [inline] br_nf_forward_ip net/bridge/br_netfilter_hooks.c:630 [inline] br_nf_forward_ip+0xc74/0x21e0 net/bridge/br_netfilter_hooks.c:571 nf_hook_entry_hookfn include/linux/netfilter.h:135 [inline] nf_hook_slow+0xbc/0x1e0 net/netfilter/core.c:512 nf_hook include/linux/netfilter.h:260 [inline] NF_HOOK include/linux/netfilter.h:303 [inline] __br_forward+0x393/0xb00 net/bridge/br_forward.c:109 deliver_clone+0x61/0xc0 net/bridge/br_forward.c:125 br_flood+0x325/0x3d0 net/bridge/br_forward.c:232 br_handle_frame_finish+0xb46/0x1670 net/bridge/br_input.c:162 br_nf_hook_thresh+0x2e9/0x370 net/bridge/br_netfilter_hooks.c:1015 br_nf_pre_routing_finish_ipv6+0x6fb/0xd80 net/bridge/br_netfilter_ipv6.c:206 NF_HOOK include/linux/netfilter.h:305 [inline] br_nf_pre_routing_ipv6+0x456/0x832 net/bridge/br_netfilter_ipv6.c:236 br_nf_pre_routing+0x1743/0x2355 net/bridge/br_netfilter_hooks.c:501 nf_hook_entry_hookfn include/linux/netfilter.h:135 [inline] nf_hook_bridge_pre net/bridge/br_input.c:223 [inline] br_handle_frame+0x806/0x133e net/bridge/br_input.c:348 __netif_receive_skb_core+0xfc1/0x3060 net/core/dev.c:4905 __netif_receive_skb_one_core+0xa8/0x1a0 net/core/dev.c:5002 __netif_receive_skb+0x2c/0x1d0 net/core/dev.c:5118 process_backlog+0x206/0x750 net/core/dev.c:5929 napi_poll net/core/dev.c:6352 [inline] net_rx_action+0x4d6/0x1030 net/core/dev.c:6418 __do_softirq+0x262/0x98c kernel/softirq.c:292 run_ksoftirqd kernel/softirq.c:603 [inline] run_ksoftirqd+0x8e/0x110 kernel/softirq.c:595 smpboot_thread_fn+0x6a3/0xa40 kernel/smpboot.c:165 kthread+0x361/0x430 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352