rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (1 ticks this GP) idle=ec8c/1/0x4000000000000000 softirq=37205/37205 fqs=1009 rcu: (detected by 0, t=10502 jiffies, g=47561, q=1198 ncpus=2) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 5301 Comm: kworker/1:6 Not tainted 6.12.0-rc3-syzkaller-00013-geca631b8fe80 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: wg-crypt-wg1 wg_packet_tx_worker RIP: 0010:__lock_is_held kernel/locking/lockdep.c:5566 [inline] RIP: 0010:lock_is_held_type+0xab/0x190 kernel/locking/lockdep.c:5897 Code: 74 41 83 bd d8 0a 00 00 00 7e 47 4c 89 eb 48 81 c3 e0 0a 00 00 31 ed 48 83 fd 31 73 24 48 89 df 4c 89 fe e8 77 02 00 00 85 c0 <75> 2a 48 ff c5 49 63 85 d8 0a 00 00 48 83 c3 28 48 39 c5 7c d8 eb RSP: 0018:ffffc90000a18178 EFLAGS: 00000046 RAX: 0000000000000000 RBX: ffff88802d7da8e0 RCX: ffff88802d7d9e00 RDX: ffff88802d7d9e00 RSI: ffff8880b872c898 RDI: ffff88802d7da8e0 RBP: 0000000000000000 R08: ffffffff8182416e R09: ffff88805c08e348 R10: dffffc0000000000 R11: ffffed100b811c6b R12: 0000000000000046 R13: ffff88802d7d9e00 R14: 00000000ffffffff R15: ffff8880b872c898 FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f31280f3608 CR3: 000000000e734000 CR4: 0000000000350ef0 Call Trace: lock_is_held include/linux/lockdep.h:249 [inline] __run_hrtimer kernel/time/hrtimer.c:1657 [inline] __hrtimer_run_queues+0x2d9/0xd50 kernel/time/hrtimer.c:1755 hrtimer_interrupt+0x396/0x990 kernel/time/hrtimer.c:1817 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1026 [inline] __sysvec_apic_timer_interrupt+0x112/0x3f0 arch/x86/kernel/apic/apic.c:1043 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1037 [inline] sysvec_apic_timer_interrupt+0x52/0xc0 arch/x86/kernel/apic/apic.c:1037 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:__xfrm_policy_check2 include/net/xfrm.h:1210 [inline] RIP: 0010:xfrm_policy_check include/net/xfrm.h:1227 [inline] RIP: 0010:xfrm6_policy_check+0xd0/0x7a0 include/net/xfrm.h:1237 Code: 48 85 c0 0f 84 5b 01 00 00 48 8d 98 b0 01 00 00 48 89 d8 48 c1 e8 03 42 80 3c 30 00 74 08 48 89 df e8 74 27 8f f7 48 83 3b 00 <0f> 84 f8 00 00 00 e8 e5 76 25 f7 48 8b 7c 24 08 31 f6 48 8b 54 24 RSP: 0018:ffffc90000a18530 EFLAGS: 00000246 RAX: 1ffff110058f355e RBX: ffff88802c79aaf0 RCX: ffff88802d7d9e00 RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffff88803242bb80 R08: ffffffff8a6f701f R09: 000000000000224e R10: 0000000000000000 R11: ffff88802d7d9e00 R12: ffff88802d241bbf R13: 0000000000000000 R14: dffffc0000000000 R15: 1ffff11005a48377 udpv6_queue_rcv_one_skb+0x5f/0x18a0 net/ipv6/udp.c:696 udp6_unicast_rcv_skb+0x230/0x370 net/ipv6/udp.c:928 ip6_protocol_deliver_rcu+0xccf/0x1580 net/ipv6/ip6_input.c:436 ip6_input_finish+0x187/0x2d0 net/ipv6/ip6_input.c:481 NF_HOOK+0x3a6/0x450 include/linux/netfilter.h:314 NF_HOOK+0x3a6/0x450 include/linux/netfilter.h:314 __netif_receive_skb_one_core net/core/dev.c:5666 [inline] __netif_receive_skb+0x1ea/0x650 net/core/dev.c:5779 process_backlog+0x662/0x15b0 net/core/dev.c:6111 __napi_poll+0xcd/0x490 net/core/dev.c:6775 napi_poll net/core/dev.c:6844 [inline] net_rx_action+0x89b/0x1240 net/core/dev.c:6966 handle_softirqs+0x2c7/0x980 kernel/softirq.c:554 do_softirq+0x11b/0x1e0 kernel/softirq.c:455 __local_bh_enable_ip+0x1bb/0x200 kernel/softirq.c:382 wg_socket_send_skb_to_peer+0x176/0x1d0 drivers/net/wireguard/socket.c:184 wg_packet_create_data_done drivers/net/wireguard/send.c:251 [inline] wg_packet_tx_worker+0x1bf/0x810 drivers/net/wireguard/send.c:276 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa65/0x1850 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f2/0x390 kernel/kthread.c:389 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 rcu: rcu_preempt kthread starved for 8433 jiffies! g47561 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:25888 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5322 [inline] __schedule+0x1895/0x4b30 kernel/sched/core.c:6682 __schedule_loop kernel/sched/core.c:6759 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6774 schedule_timeout+0x1be/0x310 kernel/time/timer.c:2615 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2045 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2247 kthread+0x2f2/0x390 kernel/kthread.c:389 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 rcu: Stack dump where RCU GP kthread last ran: CPU: 0 UID: 0 PID: 11 Comm: kworker/u8:0 Not tainted 6.12.0-rc3-syzkaller-00013-geca631b8fe80 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline] RIP: 0010:smp_call_function_many_cond+0x19f8/0x2ca0 kernel/smp.c:884 Code: 89 e6 83 e6 01 31 ff e8 56 f3 0b 00 41 83 e4 01 49 bc 00 00 00 00 00 fc ff df 75 07 e8 01 ef 0b 00 eb 38 f3 90 42 0f b6 04 23 <84> c0 75 11 41 f7 45 00 01 00 00 00 74 1e e8 e5 ee 0b 00 eb e4 44 RSP: 0018:ffffc900001076e0 EFLAGS: 00000293 RAX: 0000000000000000 RBX: 1ffff110170e8919 RCX: ffff88801d2b3c00 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc900001078e0 R08: ffffffff8188f83a R09: 1ffffffff2859100 R10: dffffc0000000000 R11: fffffbfff2859101 R12: dffffc0000000000 R13: ffff8880b87448c8 R14: ffff8880b863fc80 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f48322c1866 CR3: 000000000e734000 CR4: 0000000000350ef0 Call Trace: on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1051 on_each_cpu include/linux/smp.h:71 [inline] text_poke_sync arch/x86/kernel/alternative.c:2085 [inline] text_poke_bp_batch+0x352/0xb30 arch/x86/kernel/alternative.c:2295 text_poke_flush arch/x86/kernel/alternative.c:2486 [inline] text_poke_finish+0x30/0x50 arch/x86/kernel/alternative.c:2493 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146 static_key_enable_cpuslocked+0x136/0x260 kernel/jump_label.c:210 static_key_enable+0x1a/0x20 kernel/jump_label.c:223 toggle_allocation_gate+0xbc/0x260 mm/kfence/core.c:849 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa65/0x1850 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f2/0x390 kernel/kthread.c:389 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244