rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5094/1:b..l (detected by 0, t=10502 jiffies, g=23325, q=23) task:kworker/0:18 state:R running task stack:22200 pid: 5094 ppid: 2 flags:0x00004000 Workqueue: wg-crypt-wg0 wg_packet_encrypt_worker Call Trace: context_switch kernel/sched/core.c:5030 [inline] __schedule+0x12c4/0x45b0 kernel/sched/core.c:6376 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6780 irqentry_exit+0x53/0x80 kernel/entry/common.c:432 asm_sysvec_reschedule_ipi+0x16/0x20 arch/x86/include/asm/idtentry.h:643 RIP: 0010:lock_is_held_type+0x137/0x180 Code: 75 40 48 c7 04 24 00 00 00 00 9c 8f 04 24 f7 04 24 00 02 00 00 75 46 41 f7 c4 00 02 00 00 74 01 fb 65 48 8b 04 25 28 00 00 00 <48> 3b 44 24 08 75 3c 89 e8 48 83 c4 10 5b 41 5c 41 5d 41 5e 41 5f RSP: 0018:ffffc9000445ef98 EFLAGS: 00000206 RAX: d209567ac7a6bd00 RBX: 0000000000000002 RCX: 0000000080000000 RDX: ffff88801c070000 RSI: ffffffff8a8b3c20 RDI: ffffffff8ad8f380 RBP: 0000000000000001 R08: ffffffff8833ddd7 R09: fffffbfff1f7ec19 R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000246 R13: ffff88801c070000 R14: 00000000ffffffff R15: ffffffff8c91fb20 __skb_flow_dissect+0x690/0x66e0 net/core/flow_dissector.c:993 skb_flow_dissect_flow_keys include/linux/skbuff.h:1395 [inline] ___skb_get_hash+0x55/0x800 net/core/flow_dissector.c:1574 __skb_get_hash+0xb3/0x350 net/core/flow_dissector.c:1639 skb_get_hash include/linux/skbuff.h:1437 [inline] encrypt_packet drivers/net/wireguard/send.c:173 [inline] wg_packet_encrypt_worker+0x3b7/0x1590 drivers/net/wireguard/send.c:297 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457 kthread+0x3f6/0x4f0 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:300 rcu: rcu_preempt kthread starved for 10538 jiffies! g23325 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->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:R running task stack:26168 pid: 15 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5030 [inline] __schedule+0x12c4/0x45b0 kernel/sched/core.c:6376 schedule+0x11b/0x1f0 kernel/sched/core.c:6459 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1914 rcu_gp_fqs_loop+0x2bf/0x1080 kernel/rcu/tree.c:1972 rcu_gp_kthread+0xa4/0x360 kernel/rcu/tree.c:2145 kthread+0x3f6/0x4f0 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:300 rcu: Stack dump where RCU GP kthread last ran: NMI backtrace for cpu 0 CPU: 0 PID: 5526 Comm: syz-executor.4 Not tainted 5.15.156-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106 nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62 trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline] rcu_check_gp_kthread_starvation+0x1d2/0x240 kernel/rcu/tree_stall.h:487 print_other_cpu_stall+0x137a/0x14d0 kernel/rcu/tree_stall.h:592 check_cpu_stall kernel/rcu/tree_stall.h:745 [inline] rcu_pending kernel/rcu/tree.c:3932 [inline] rcu_sched_clock_irq+0xa38/0x1150 kernel/rcu/tree.c:2619 update_process_times+0x196/0x200 kernel/time/timer.c:1818 tick_sched_handle kernel/time/tick-sched.c:254 [inline] tick_sched_timer+0x386/0x550 kernel/time/tick-sched.c:1473 __run_hrtimer kernel/time/hrtimer.c:1686 [inline] __hrtimer_run_queues+0x55b/0xcf0 kernel/time/hrtimer.c:1750 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1812 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1085 [inline] __sysvec_apic_timer_interrupt+0x139/0x470 arch/x86/kernel/apic/apic.c:1102 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1096 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:__syscall_enter_from_user_work kernel/entry/common.c:93 [inline] RIP: 0010:syscall_enter_from_user_mode+0x37/0x240 kernel/entry/common.c:114 Code: 49 89 fe 48 8b 7c 24 30 e8 46 f6 ff ff e9 8d 01 00 00 e9 91 01 00 00 e8 27 36 69 f7 e8 12 34 69 f7 fb 65 4c 8b 3d e9 c6 e4 75 <49> 8b 5f 08 f6 c3 3f 0f 84 ce 00 00 00 f6 c3 20 74 17 4c 89 f7 e8 RSP: 0018:ffffc90003167ef8 EFLAGS: 00000282 RAX: df55b4abdf48c100 RBX: ffffc90003167f30 RCX: ffffffff913edf03 RDX: dffffc0000000000 RSI: ffffffff8a8b2980 RDI: ffffffff8ad8f380 RBP: ffffc90003167f48 R08: ffffffff8186dd10 R09: fffffbfff1bc8b5e R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000000 R13: 000000000000000f R14: ffffc90003167f58 R15: ffff88807ea55940 do_syscall_64+0x1e/0xb0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f8bd7148309 Code: 64 c7 00 16 00 00 00 b8 ff ff ff ff c3 0f 1f 40 00 90 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 c7 c0 0f 00 00 00 0f 05 <0f> 1f 80 00 00 00 00 48 81 ec 48 01 00 00 49 89 d0 64 48 8b 04 25 RSP: 002b:00007ffd326c77c0 EFLAGS: 00000202 ORIG_RAX: 000000000000000f RAX: ffffffffffffffda RBX: 00007f8bd72b2f80 RCX: 00007f8bd7148309 RDX: 00007ffd326c77c0 RSI: 00007ffd326c78f0 RDI: 0000000000000021 RBP: 00007f8bd72b4980 R08: 0000000000000000 R09: 0000000000000010 R10: 0000000000000000 R11: 0000000000000202 R12: 00000000000285e2 R13: 000000000002834a R14: 00007ffd326c7f90 R15: 00007f8bd713bcb0 sched: RT throttling activated