watchdog: BUG: soft lockup - CPU#0 stuck for 144s! [syz.1.938:10493] Modules linked in: irq event stamp: 13490889 hardirqs last enabled at (13490888): [] irqentry_exit+0x59e/0x620 kernel/entry/common.c:242 hardirqs last disabled at (13490889): [] sysvec_apic_timer_interrupt+0xe/0xc0 arch/x86/kernel/apic/apic.c:1056 softirqs last enabled at (12549244): [] __do_softirq kernel/softirq.c:656 [inline] softirqs last enabled at (12549244): [] invoke_softirq kernel/softirq.c:496 [inline] softirqs last enabled at (12549244): [] __irq_exit_rcu+0x5f/0x150 kernel/softirq.c:723 softirqs last disabled at (12549247): [] __do_softirq kernel/softirq.c:656 [inline] softirqs last disabled at (12549247): [] invoke_softirq kernel/softirq.c:496 [inline] softirqs last disabled at (12549247): [] __irq_exit_rcu+0x5f/0x150 kernel/softirq.c:723 CPU: 0 UID: 0 PID: 10493 Comm: syz.1.938 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 RIP: 0010:unwind_next_frame+0x484/0x23c0 arch/x86/kernel/unwind_orc.c:520 Code: d2 84 c0 48 0f 45 d1 48 89 15 b8 b3 ab 11 48 85 d2 0f 84 40 02 00 00 4c 8d 62 04 4c 8d 6a 05 4c 89 e0 48 c1 e8 03 0f b6 04 28 <84> c0 0f 85 66 18 00 00 4c 89 e8 48 c1 e8 03 0f b6 04 28 84 c0 0f RSP: 0018:ffffc90000007498 EFLAGS: 00000a02 RAX: 0000000000000000 RBX: ffffffff9099c888 RCX: ffffffff9099c890 RDX: ffffffff914dd3c6 RSI: ffffffff914dd390 RDI: ffffffff8c27ae20 RBP: dffffc0000000000 R08: 000000000000000d R09: ffffffff8e7602e0 R10: ffffc90000007088 R11: fffff52000000e13 R12: ffffffff914dd3ca R13: ffffffff914dd3cb R14: ffffc90000007568 R15: ffffffff9099c88c FS: 00007f3945a646c0(0000) GS:ffff888125463000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f8835058a90 CR3: 0000000075ed0000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000200000000300 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2692 [inline] slab_free mm/slub.c:6143 [inline] kmem_cache_free+0x187/0x630 mm/slub.c:6273 kfree_skb_reason include/linux/skbuff.h:1322 [inline] __netif_receive_skb_core+0x2c10/0x31a0 net/core/dev.c:6141 __netif_receive_skb_one_core net/core/dev.c:6165 [inline] __netif_receive_skb net/core/dev.c:6280 [inline] process_backlog+0x76d/0x1950 net/core/dev.c:6631 __napi_poll+0xae/0x340 net/core/dev.c:7695 napi_poll net/core/dev.c:7758 [inline] net_rx_action+0x627/0xf70 net/core/dev.c:7910 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:preempt_schedule_irq+0x48/0xa0 kernel/sched/core.c:7234 Code: 49 be 00 00 00 00 00 fc ff df eb 09 48 f7 03 10 00 00 00 74 53 bf 01 00 00 00 e8 c3 30 e5 f5 e8 3e bb 1e f6 fb bf 01 00 00 00 53 a6 ff ff 9c 58 fa a9 00 02 00 00 74 05 e8 14 bd 1e f6 bf 01 RSP: 0018:ffffc9000dcefbd0 EFLAGS: 00000206 RAX: 000000000000e299 RBX: 0000000000000000 RCX: 0000000000000001 RDX: 0000000000000007 RSI: ffffffff8def2f52 RDI: 0000000000000001 RBP: 0000000000000000 R08: ffffffff90118eb7 R09: 1ffffffff20231d6 R10: dffffc0000000000 R11: fffffbfff20231d7 R12: 0000000000000000 R13: 0000000000000000 R14: dffffc0000000000 R15: 0000000000000000 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:up_read+0x0/0x20 kernel/locking/rwsem.c:1631 Code: fd ff ff 48 c7 c7 c0 c1 11 90 e8 cb c7 8e 00 e9 87 fd ff ff 66 0f 1f 44 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 53 48 89 fb 48 83 c7 70 48 8b 74 24 08 e8 ea a0 00 00 RSP: 0018:ffffc9000dcefcf8 EFLAGS: 00000282 RAX: 1ffff1100a8708b9 RBX: ffff888054383c80 RCX: dffffc0000000000 RDX: ffffc90005521000 RSI: 000000000000224b RDI: ffff88802bedc008 RBP: ffffc9000dcefee0 R08: ffffc9000dcefc87 R09: 1ffff92001b9df90 R10: dffffc0000000000 R11: fffff52001b9df91 R12: 1ffff92001b9dfb0 R13: ffff8880813b3ed0 R14: ffff8880813b4118 R15: ffff888054383c80 __do_sys_perf_event_open kernel/events/core.c:14131 [inline] __se_sys_perf_event_open+0x1992/0x1d60 kernel/events/core.c:13767 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: 0033:0x7f3944b9c799 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:00007f3945a64028 EFLAGS: 00000246 ORIG_RAX: 000000000000012a RAX: ffffffffffffffda RBX: 00007f3944e15fa0 RCX: 00007f3944b9c799 RDX: ffffffffffffffff RSI: 0000000000000000 RDI: 0000200000000040 RBP: 00007f3944c32bd9 R08: 0000000000000001 R09: 0000000000000000 R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000 R13: 00007f3944e16038 R14: 00007f3944e15fa0 R15: 00007fff792f6eb8 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 7602 Comm: kworker/u8:23 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 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 74 e2 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 1f de 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 03 de RSP: 0018:ffffc9001afc7720 EFLAGS: 00000293 RAX: ffffffff81b9adcd RBX: 1ffff110170c8515 RCX: ffff888026ee9e40 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc9001afc7860 R08: ffffffff90118eb7 R09: 1ffffffff20231d6 R10: dffffc0000000000 R11: fffffbfff20231d7 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: 00007f5478a42286 CR3: 000000000e54c000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000200000000300 DR2: 0000000000000000 DR3: 0000000000000000 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:2746 [inline] smp_text_poke_batch_finish+0x5f5/0x1160 arch/x86/kernel/alternative.c:2956 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146 static_key_disable_cpuslocked+0xc5/0x1a0 kernel/jump_label.c:240 static_key_disable+0x1a/0x20 kernel/jump_label.c:248 toggle_allocation_gate+0x1fe/0x290 mm/kfence/core.c:907 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:467 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245