watchdog: BUG: soft lockup - CPU#0 stuck for 143s! [syz.7.9377:12392] Modules linked in: irq event stamp: 13205697 hardirqs last enabled at (13205696): [] irqentry_exit+0x59e/0x620 kernel/entry/common.c:242 hardirqs last disabled at (13205697): [] sysvec_apic_timer_interrupt+0xe/0xc0 arch/x86/kernel/apic/apic.c:1056 softirqs last enabled at (13181902): [] __do_softirq kernel/softirq.c:656 [inline] softirqs last enabled at (13181902): [] invoke_softirq kernel/softirq.c:496 [inline] softirqs last enabled at (13181902): [] __irq_exit_rcu+0x5f/0x150 kernel/softirq.c:723 softirqs last disabled at (13181905): [] __do_softirq kernel/softirq.c:656 [inline] softirqs last disabled at (13181905): [] invoke_softirq kernel/softirq.c:496 [inline] softirqs last disabled at (13181905): [] __irq_exit_rcu+0x5f/0x150 kernel/softirq.c:723 CPU: 0 UID: 0 PID: 12392 Comm: syz.7.9377 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/27/2026 RIP: 0010:alloc_from_pcs mm/slub.c:4719 [inline] RIP: 0010:slab_alloc_node mm/slub.c:4854 [inline] RIP: 0010:kmem_cache_alloc_noprof+0x1d1/0x650 mm/slub.c:4876 Code: 24 18 4d 8b 3e e8 df 25 8a 09 41 89 c4 83 f8 08 0f 83 07 03 00 00 4a 8b 04 e5 90 d7 1a 8e 4a 8d 2c 38 4a 8b 44 38 38 8b 48 18 <85> c9 0f 84 97 01 00 00 4c 8b 7c 24 18 ff c9 48 8b 7c c8 20 45 84 RSP: 0018:ffffc90000007768 EFLAGS: 00000293 RAX: ffff88804bd1bc00 RBX: 0000000000002820 RCX: 000000000000000b RDX: 0000000066675a99 RSI: ffffffff8c27b3e0 RDI: ffffffff8c27b3a0 RBP: ffff8880b86430b0 R08: ffffffff8223e66a R09: ffff8880b86430b0 R10: ffffc90000007388 R11: fffff52000000e73 R12: 0000000000000000 R13: 0000000000000001 R14: ffff88814041adc0 R15: ffffffff931e00b0 FS: 00007f2611a636c0(0000) GS:ffff888125463000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c3a61ef CR3: 000000003a7fe000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000200000000300 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: __build_skb+0x62/0x440 net/core/skbuff.c:492 build_skb+0x23/0x250 net/core/skbuff.c:508 virtnet_build_skb drivers/net/virtio_net.c:834 [inline] page_to_skb+0x161/0x870 drivers/net/virtio_net.c:876 receive_mergeable drivers/net/virtio_net.c:2497 [inline] receive_buf+0x546/0x1900 drivers/net/virtio_net.c:2643 virtnet_receive_packets drivers/net/virtio_net.c:2970 [inline] virtnet_receive drivers/net/virtio_net.c:2994 [inline] virtnet_poll+0x219e/0x2f90 drivers/net/virtio_net.c:3083 __napi_poll+0xae/0x340 net/core/dev.c:7692 napi_poll net/core/dev.c:7755 [inline] net_rx_action+0x627/0xf70 net/core/dev.c:7912 handle_softirqs+0x22a/0x870 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0x5f/0x150 kernel/softirq.c:723 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1056 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:__read_once_word_nocheck+0x0/0x10 include/asm-generic/rwonce.h:67 Code: 26 47 b9 00 48 ba 00 00 00 00 00 fc ff df e9 88 fc ff ff 0f 1f 80 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <48> 8b 07 e9 48 2b 3a 0a cc cc cc cc cc cc cc cc 90 90 90 90 90 90 RSP: 0018:ffffc9000481ea70 EFLAGS: 00000202 RAX: ffffc9000481ff01 RBX: ffffc90004820000 RCX: 1ffff92000903d01 RDX: ffffffff909ce96a RSI: 0000000000000003 RDI: ffffc9000481ffc8 RBP: 1ffff92000903d6b R08: 0000000000000022 R09: ffffffff8e75e3e0 R10: ffffc9000481e688 R11: fffff52000903cd3 R12: ffffc90004818000 R13: ffffc9000481eb50 R14: ffffc9000481eb48 R15: ffffc9000481ff48 deref_stack_regs arch/x86/kernel/unwind_orc.c:437 [inline] unwind_next_frame+0x104d/0x23c0 arch/x86/kernel/unwind_orc.c:611 arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122 kasan_save_stack+0x3e/0x60 mm/kasan/common.c:57 kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:556 __call_rcu_common kernel/rcu/tree.c:3131 [inline] call_rcu+0xee/0x890 kernel/rcu/tree.c:3251 context_switch kernel/sched/core.c:5298 [inline] __schedule+0x15e5/0x52d0 kernel/sched/core.c:6908 preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7235 irqentry_exit+0x599/0x620 kernel/entry/common.c:239 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:orc_find arch/x86/kernel/unwind_orc.c:229 [inline] RIP: 0010:unwind_next_frame+0x223/0x23c0 arch/x86/kernel/unwind_orc.c:510 Code: 86 78 04 00 00 44 89 f8 4c 8d 2c 85 60 84 52 91 4c 89 e8 48 c1 e8 03 0f b6 04 28 84 c0 48 89 eb 0f 85 25 1c 00 00 45 8b 6d 00 <44> 89 f8 ff c0 48 8d 2c 85 60 84 52 91 48 89 e8 48 c1 e8 03 0f b6 RSP: 0018:ffffc9000481f298 EFLAGS: 00000246 RAX: 0000000000000000 RBX: dffffc0000000000 RCX: 0000000080000000 RDX: 00000000000ab1bc RSI: ffffffff8c27b3e0 RDI: ffffffff8c27b3a0 RBP: dffffc0000000000 R08: ffffffff81767de5 R09: ffffffff8e75e3e0 R10: ffffc9000481ee88 R11: fffff52000903dd3 R12: ffffffff8224d808 R13: 000000000003b062 R14: ffffc9000481f368 R15: 00000000000124d8 arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122 save_stack+0x122/0x230 mm/page_owner.c:165 __set_page_owner+0x8d/0x4c0 mm/page_owner.c:341 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x231/0x280 mm/page_alloc.c:1889 prep_new_page mm/page_alloc.c:1897 [inline] get_page_from_freelist+0x24dc/0x2580 mm/page_alloc.c:3962 __alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5250 alloc_slab_page mm/slub.c:3296 [inline] allocate_slab+0x77/0x660 mm/slub.c:3485 new_slab mm/slub.c:3543 [inline] refill_objects+0x331/0x3c0 mm/slub.c:7178 __pcs_replace_empty_main+0x2f9/0x5e0 mm/slub.c:-1 alloc_from_pcs mm/slub.c:4720 [inline] slab_alloc_node mm/slub.c:4854 [inline] kmem_cache_alloc_node_noprof+0x441/0x690 mm/slub.c:4921 perf_event_alloc+0x1cb/0x2e30 kernel/events/core.c:13293 __do_sys_perf_event_open kernel/events/core.c:13927 [inline] __se_sys_perf_event_open+0x7a9/0x1d60 kernel/events/core.c:13808 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f2610b9c799 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f2611a63028 EFLAGS: 00000246 ORIG_RAX: 000000000000012a RAX: ffffffffffffffda RBX: 00007f2610e15fa0 RCX: 00007f2610b9c799 RDX: ffffffffffffffff RSI: 0000000000000000 RDI: 0000200000000180 RBP: 00007f2610c32c99 R08: 000000000000000a R09: 0000000000000000 R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000 R13: 00007f2610e16038 R14: 00007f2610e15fa0 R15: 00007ffd75cab1d8 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 24539 Comm: kworker/u8:19 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/27/2026 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline] RIP: 0010:smp_call_function_many_cond+0xce5/0x12c0 kernel/smp.c:877 Code: 45 8b 2c 24 44 89 ee 83 e6 01 31 ff e8 24 e6 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 cf e1 0b 00 eb 38 f3 90 <42> 0f b6 04 2b 84 c0 75 11 41 f7 04 24 01 00 00 00 74 1e e8 b3 e1 RSP: 0018:ffffc90005a17720 EFLAGS: 00000293 RAX: ffffffff81b9bbfd RBX: 1ffff110170c8515 RCX: ffff8880a0381e80 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc90005a17860 R08: ffffffff90118db7 R09: 1ffffffff20231b6 R10: dffffc0000000000 R11: fffffbfff20231b7 R12: ffff8880b86428a8 R13: dffffc0000000000 R14: ffff8880b873bf80 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff888125563000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffce2e14970 CR3: 000000000e54c000 CR4: 00000000003526f0 DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000200000000300 DR3: 0000200000000300 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1043 on_each_cpu include/linux/smp.h:72 [inline] smp_text_poke_sync_each_cpu arch/x86/kernel/alternative.c:2761 [inline] smp_text_poke_batch_finish+0x5f5/0x1160 arch/x86/kernel/alternative.c:2971 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146 static_key_enable_cpuslocked+0x128/0x240 kernel/jump_label.c:210 static_key_enable+0x1a/0x20 kernel/jump_label.c:223 toggle_allocation_gate+0xab/0x290 mm/kfence/core.c:900 process_one_work kernel/workqueue.c:3275 [inline] process_scheduled_works+0xb02/0x1830 kernel/workqueue.c:3358 worker_thread+0xa50/0xfc0 kernel/workqueue.c:3439 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245