watchdog: BUG: soft lockup - CPU#1 stuck for 225s! [syz.0.4336:16936]
Modules linked in:
CPU: 1 PID: 16936 Comm: syz.0.4336 Tainted: G        W          syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:trylock_clear_pending kernel/locking/qspinlock_paravirt.h:121 [inline]
RIP: 0010:pv_wait_head_or_lock kernel/locking/qspinlock_paravirt.h:435 [inline]
RIP: 0010:__pv_queued_spin_lock_slowpath+0x596/0xc40 kernel/locking/qspinlock.c:511
Code: 00 41 c6 45 00 00 41 0f b6 04 17 84 c0 0f 85 46 01 00 00 48 8b 44 24 10 c6 00 01 41 bd 00 80 ff ff eb 07 f3 90 41 ff c5 74 5b <41> 0f b6 04 16 84 c0 75 35 80 3b 00 75 eb 48 89 df be 02 00 00 00
RSP: 0018:ffffc900001b0200 EFLAGS: 00000286
RAX: 0000000000000000 RBX: ffffffff875a4fac RCX: ffffffff84f49de2
RDX: dffffc0000000000 RSI: 0000000000000003 RDI: ffffffff875a4fac
RBP: ffffc900001b02f0 R08: dffffc0000000000 R09: fffffbfff0eb49f6
R10: fffffbfff0eb49f6 R11: 1ffffffff0eb49f5 R12: 1ffff1103ee20001
R13: 00000000ffffaa4b R14: 1ffffffff0eb49f5 R15: 1ffffffff0eb49f5
FS:  00007f2801aa46c0(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c2f2721 CR3: 00000001570b6000 CR4: 00000000003506a0
DR0: 0000200000000300 DR1: 0000200000000300 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:591 [inline]
 queued_spin_lock_slowpath+0x47/0x50 arch/x86/include/asm/qspinlock.h:51
 queued_spin_lock include/asm-generic/qspinlock.h:114 [inline]
 do_raw_spin_lock include/linux/spinlock.h:187 [inline]
 __raw_spin_lock include/linux/spinlock_api_smp.h:134 [inline]
 _raw_spin_lock+0xd8/0xe0 kernel/locking/spinlock.c:154
 spin_lock include/linux/spinlock.h:351 [inline]
 __dev_xmit_skb net/core/dev.c:3950 [inline]
 __dev_queue_xmit+0xbbc/0x3420 net/core/dev.c:4323
 dev_queue_xmit include/linux/netdevice.h:3085 [inline]
 neigh_resolve_output+0x6f5/0x7f0 net/core/neighbour.c:1563
 neigh_output include/net/neighbour.h:552 [inline]
 ip6_finish_output2+0x1607/0x1870 net/ipv6/ip6_output.c:138
 __ip6_finish_output net/ipv6/ip6_output.c:205 [inline]
 ip6_finish_output+0x5f9/0xbb0 net/ipv6/ip6_output.c:216
 NF_HOOK_COND include/linux/netfilter.h:294 [inline]
 ip6_output+0x1d1/0x3b0 net/ipv6/ip6_output.c:237
 dst_output include/net/dst.h:453 [inline]
 NF_HOOK include/linux/netfilter.h:305 [inline]
 ndisc_send_skb+0x7e3/0xcf0 net/ipv6/ndisc.c:513
 ndisc_send_rs+0x670/0x870 net/ipv6/ndisc.c:723
 addrconf_rs_timer+0x2c7/0x600 net/ipv6/addrconf.c:4005
 call_timer_fn+0x46/0x2a0 kernel/time/timer.c:1553
 expire_timers kernel/time/timer.c:1604 [inline]
 __run_timers+0x644/0x9b0 kernel/time/timer.c:1875
 run_timer_softirq+0x6a/0xf0 kernel/time/timer.c:1888
 handle_softirqs+0x1d7/0x600 kernel/softirq.c:642
 __do_softirq kernel/softirq.c:680 [inline]
 invoke_softirq kernel/softirq.c:497 [inline]
 __irq_exit_rcu+0x52/0xf0 kernel/softirq.c:729
 irq_exit_rcu+0x9/0x10 kernel/softirq.c:741
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
 sysvec_apic_timer_interrupt+0xa9/0xc0 arch/x86/kernel/apic/apic.c:1118
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1b/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:csd_lock_wait kernel/smp.c:453 [inline]
RIP: 0010:smp_call_function_many_cond+0x872/0x960 kernel/smp.c:998
Code: 41 8b 1f 89 de 83 e6 01 31 ff e8 99 65 09 00 83 e3 01 48 bb 00 00 00 00 00 fc ff df 75 0a e8 65 61 09 00 e9 38 ff ff ff f3 90 <41> 0f b6 44 1d 00 84 c0 75 14 41 f7 07 01 00 00 00 0f 84 1a ff ff
RSP: 0018:ffffc9000b727960 EFLAGS: 00000246
RAX: ffffffff8166c8be RBX: dffffc0000000000 RCX: 0000000000080000
RDX: ffffc9000e3e9000 RSI: 000000000007ffff RDI: 0000000000080000
RBP: ffffc9000b727a98 R08: dffffc0000000000 R09: fffff520016e4f1d
R10: 0000000000000000 R11: 1ffff920016e4f1c R12: 1ffff1103ee27218
R13: 1ffff1103ee07ae1 R14: 0000000000000000 R15: ffff8881f703d708
 on_each_cpu_cond_mask+0x43/0x80 kernel/smp.c:1165
 on_each_cpu include/linux/smp.h:71 [inline]
 text_poke_sync arch/x86/kernel/alternative.c:1574 [inline]
 text_poke_bp_batch+0x1cc/0x580 arch/x86/kernel/alternative.c:1774
 text_poke_flush arch/x86/kernel/alternative.c:1965 [inline]
 text_poke_finish+0x1a/0x30 arch/x86/kernel/alternative.c:1972
 arch_jump_label_transform_apply+0x15/0x30 arch/x86/kernel/jump_label.c:146
 __jump_label_update+0x37c/0x3a0 kernel/jump_label.c:451
 jump_label_update+0x39b/0x450 kernel/jump_label.c:797
 __static_key_slow_dec_cpuslocked+0xf7/0x150 kernel/jump_label.c:244
 __static_key_slow_dec kernel/jump_label.c:251 [inline]
 static_key_slow_dec+0x45/0x90 kernel/jump_label.c:266
 sw_perf_event_destroy+0x99/0x2d0 kernel/events/core.c:9852
 _free_event+0x9cd/0xce0 kernel/events/core.c:5045
 put_event kernel/events/core.c:5139 [inline]
 perf_pending_task+0x391/0x4e0 kernel/events/core.c:6679
 task_work_run+0x1db/0x240 kernel/task_work.c:203
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop+0x9b/0xb0 kernel/entry/common.c:177
 exit_to_user_mode_prepare+0x87/0xd0 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
 syscall_exit_to_user_mode+0x1a/0x30 kernel/entry/common.c:303
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:87
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f2800b8f749
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f2801aa3fe8 EFLAGS: 00000206 ORIG_RAX: 0000000000000038
RAX: fffffffffffffff2 RBX: 00007f2800de5fa0 RCX: 00007f2800b8f749
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000630c1000
RBP: 00007f2800c13f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 00007f2800de6038 R14: 00007f2800de5fa0 R15: 00007ffeeb573f28
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 16950 Comm: syz.1.4339 Tainted: G        W          syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:native_halt arch/x86/include/asm/irqflags.h:57 [inline]
RIP: 0010:halt arch/x86/include/asm/irqflags.h:98 [inline]
RIP: 0010:kvm_wait+0xcc/0x140 arch/x86/kernel/kvm.c:1058
Code: 20 f6 44 24 21 02 75 24 48 89 f8 48 c1 e8 03 42 0f b6 04 30 84 c0 75 48 0f b6 07 40 38 f0 75 a6 66 90 0f 00 2d 95 96 13 04 f4 <eb> 9a fa 48 89 f8 48 c1 e8 03 42 0f b6 04 30 84 c0 75 3f 0f b6 07
RSP: 0018:ffffc9000af2f3c0 EFLAGS: 00000046
RAX: 0000000000000003 RBX: ffff888132de1d60 RCX: ffffffff84f49de2
RDX: dffffc0000000000 RSI: 0000000000000003 RDI: ffff888132de1d60
RBP: ffffc9000af2f450 R08: dffffc0000000000 R09: ffffed10265bc3ad
R10: ffffed10265bc3ad R11: 1ffff110265bc3ac R12: 1ffff1103ee00001
R13: ffff8881f7038cf4 R14: dffffc0000000000 R15: 1ffff920015e5e78
FS:  00007fe815cbc6c0(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 0000000133660000 CR4: 00000000003506b0
DR0: 0000000000000000 DR1: 0000200000000300 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <TASK>
 pv_wait arch/x86/include/asm/paravirt.h:603 [inline]
 pv_wait_head_or_lock kernel/locking/qspinlock_paravirt.h:470 [inline]
 __pv_queued_spin_lock_slowpath+0x690/0xc40 kernel/locking/qspinlock.c:511
 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:591 [inline]
 queued_spin_lock_slowpath+0x47/0x50 arch/x86/include/asm/qspinlock.h:51
 queued_spin_lock include/asm-generic/qspinlock.h:114 [inline]
 do_raw_spin_lock include/linux/spinlock.h:187 [inline]
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:111 [inline]
 _raw_spin_lock_irqsave+0x108/0x110 kernel/locking/spinlock.c:162
 trie_delete_elem+0x95/0x720 kernel/bpf/lpm_trie.c:467
 bpf_prog_471848dd901c6738+0x45/0x49
 bpf_dispatcher_nop_func include/linux/bpf.h:987 [inline]
 __bpf_prog_run include/linux/filter.h:603 [inline]
 bpf_prog_run include/linux/filter.h:610 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:2283 [inline]
 bpf_trace_run2+0xff/0x250 kernel/trace/bpf_trace.c:2322
 __bpf_trace_contention_end+0xb/0x10 include/trace/events/lock.h:122
 trace_contention_end include/trace/events/lock.h:122 [inline]
 __pv_queued_spin_lock_slowpath+0xbff/0xc40 kernel/locking/qspinlock.c:560
 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:591 [inline]
 queued_spin_lock_slowpath+0x47/0x50 arch/x86/include/asm/qspinlock.h:51
 queued_spin_lock include/asm-generic/qspinlock.h:114 [inline]
 do_raw_spin_lock include/linux/spinlock.h:187 [inline]
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:111 [inline]
 _raw_spin_lock_irqsave+0x108/0x110 kernel/locking/spinlock.c:162
 trie_delete_elem+0x95/0x720 kernel/bpf/lpm_trie.c:467
 bpf_prog_471848dd901c6738+0x45/0x49
 bpf_dispatcher_nop_func include/linux/bpf.h:987 [inline]
 __bpf_prog_run include/linux/filter.h:603 [inline]
 bpf_prog_run include/linux/filter.h:610 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:2283 [inline]
 bpf_trace_run1+0xf0/0x240 kernel/trace/bpf_trace.c:2321
 __bpf_trace_qdisc_reset+0x1d/0x30 include/trace/events/qdisc.h:77
 __traceiter_qdisc_reset+0x7a/0xc0 include/trace/events/qdisc.h:77
 trace_qdisc_reset include/trace/events/qdisc.h:77 [inline]
 qdisc_reset+0x478/0x4c0 net/sched/sch_generic.c:1029
 qdisc_reset_all_tx_gt include/net/sch_generic.h:738 [inline]
 netif_set_real_num_tx_queues+0x59f/0x7f0 net/core/dev.c:2973
 tun_set_real_num_queues drivers/net/tun.c:589 [inline]
 __tun_detach+0xb31/0x1460 drivers/net/tun.c:673
 tun_set_queue drivers/net/tun.c:2993 [inline]
 __tun_chr_ioctl+0xaec/0x1e70 drivers/net/tun.c:3097
 tun_chr_ioctl+0x2a/0x40 drivers/net/tun.c:3401
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl+0x12f/0x1b0 fs/ioctl.c:856
 __x64_sys_ioctl+0x7b/0x90 fs/ioctl.c:856
 x64_sys_call+0x58b/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:17
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fe814d8f749
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fe815cbc038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fe814fe5fa0 RCX: 00007fe814d8f749
RDX: 0000200000000100 RSI: 00000000400454d9 RDI: 000000000000000c
RBP: 00007fe814e13f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fe814fe6038 R14: 00007fe814fe5fa0 R15: 00007ffef1f9fce8
 </TASK>