rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 1-....: (10499 ticks this GP) idle=d56/1/0x4000000000000000 softirq=153213/153213 fqs=36 (t=10500 jiffies g=288809 q=167) rcu: rcu_preempt kthread starved for 628 jiffies! g288809 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=0 rcu: Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior. rcu: RCU grace-period kthread stack dump: task:rcu_preempt state:I stack:29000 pid: 11 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:3774 [inline] __schedule+0x893/0x2130 kernel/sched/core.c:4523 schedule+0xcf/0x270 kernel/sched/core.c:4601 schedule_timeout+0x148/0x250 kernel/time/timer.c:1871 rcu_gp_fqs_loop kernel/rcu/tree.c:1925 [inline] rcu_gp_kthread+0xb4c/0x1c90 kernel/rcu/tree.c:2099 kthread+0x3af/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296 NMI backtrace for cpu 1 CPU: 1 PID: 2999 Comm: kworker/1:2 Not tainted 5.10.0-rc2-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: wg-crypt-wg0 wg_packet_tx_worker Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x107/0x163 lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x44/0xd7 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x1b3/0x230 lib/nmi_backtrace.c:62 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline] rcu_dump_cpu_stacks+0x1e3/0x21e kernel/rcu/tree_stall.h:318 print_cpu_stall kernel/rcu/tree_stall.h:551 [inline] check_cpu_stall kernel/rcu/tree_stall.h:625 [inline] rcu_pending kernel/rcu/tree.c:3694 [inline] rcu_sched_clock_irq.cold+0x4db/0xded kernel/rcu/tree.c:2567 update_process_times+0x77/0xd0 kernel/time/timer.c:1709 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:176 tick_sched_timer+0x1d1/0x2a0 kernel/time/tick-sched.c:1328 __run_hrtimer kernel/time/hrtimer.c:1519 [inline] __hrtimer_run_queues+0x1ce/0xea0 kernel/time/hrtimer.c:1583 hrtimer_interrupt+0x334/0x940 kernel/time/hrtimer.c:1645 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1080 [inline] __sysvec_apic_timer_interrupt+0x146/0x540 arch/x86/kernel/apic/apic.c:1097 asm_call_irq_on_stack+0xf/0x20 __run_sysvec_on_irqstack arch/x86/include/asm/irq_stack.h:37 [inline] run_sysvec_on_irqstack_cond arch/x86/include/asm/irq_stack.h:89 [inline] sysvec_apic_timer_interrupt+0xbd/0x100 arch/x86/kernel/apic/apic.c:1091 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:631 RIP: 0010:__sanitizer_cov_trace_const_cmp4+0x0/0x20 kernel/kcov.c:284 Code: 66 2e 0f 1f 84 00 00 00 00 00 48 8b 0c 24 0f b7 d6 0f b7 f7 bf 03 00 00 00 e9 cc fe ff ff 66 90 66 2e 0f 1f 84 00 00 00 00 00 <48> 8b 0c 24 89 f2 89 fe bf 05 00 00 00 e9 ae fe ff ff 0f 1f 40 00 RSP: 0018:ffffc90001b07580 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 00000000efccf590 RCX: ffff888012d6d328 RDX: ffff888019be0000 RSI: 00000000efccf590 RDI: 0000000000000000 RBP: ffff888012d6d340 R08: 0000000000000001 R09: 0000000000000003 R10: 0000000000000000 R11: 0000000000000000 R12: ffff888012d6d000 R13: dffffc0000000000 R14: ffff8880632aee90 R15: ffff888012d6d338 fq_codel_dequeue+0xd8/0x1f50 net/sched/sch_fq_codel.c:297 dequeue_skb net/sched/sch_generic.c:263 [inline] qdisc_restart net/sched/sch_generic.c:366 [inline] __qdisc_run+0x1ae/0x15e0 net/sched/sch_generic.c:384 __dev_xmit_skb net/core/dev.c:3791 [inline] __dev_queue_xmit+0x2642/0x2da0 net/core/dev.c:4108 neigh_hh_output include/net/neighbour.h:498 [inline] neigh_output include/net/neighbour.h:507 [inline] ip_finish_output2+0xe95/0x2120 net/ipv4/ip_output.c:230 __ip_finish_output net/ipv4/ip_output.c:308 [inline] __ip_finish_output+0x7cf/0xd10 net/ipv4/ip_output.c:290 ip_finish_output+0x34/0x1f0 net/ipv4/ip_output.c:318 NF_HOOK_COND include/linux/netfilter.h:290 [inline] ip_output+0x196/0x310 net/ipv4/ip_output.c:432 dst_output include/net/dst.h:441 [inline] ip_local_out+0xaf/0x1a0 net/ipv4/ip_output.c:126 iptunnel_xmit+0x5a3/0x9c0 net/ipv4/ip_tunnel_core.c:82 send4+0x4bf/0xe00 drivers/net/wireguard/socket.c:85 wg_socket_send_skb_to_peer+0x192/0x220 drivers/net/wireguard/socket.c:174 wg_packet_create_data_done drivers/net/wireguard/send.c:252 [inline] wg_packet_tx_worker+0x2f9/0x980 drivers/net/wireguard/send.c:280 process_one_work+0x933/0x15a0 kernel/workqueue.c:2272 worker_thread+0x64c/0x1120 kernel/workqueue.c:2418 kthread+0x3af/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296