watchdog: BUG: soft lockup - CPU#0 stuck for 144s! [syz.8.3586:18935] Modules linked in: irq event stamp: 5133197 hardirqs last enabled at (5133196): [] irqentry_exit+0x74/0x90 kernel/entry/common.c:200 hardirqs last disabled at (5133197): [] sysvec_apic_timer_interrupt+0xe/0xc0 arch/x86/kernel/apic/apic.c:1050 softirqs last enabled at (4868596): [] __do_softirq kernel/softirq.c:613 [inline] softirqs last enabled at (4868596): [] invoke_softirq kernel/softirq.c:453 [inline] softirqs last enabled at (4868596): [] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680 softirqs last disabled at (4868599): [] __do_softirq kernel/softirq.c:613 [inline] softirqs last disabled at (4868599): [] invoke_softirq kernel/softirq.c:453 [inline] softirqs last disabled at (4868599): [] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680 CPU: 0 UID: 0 PID: 18935 Comm: syz.8.3586 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:rcu_preempt_read_exit kernel/rcu/tree_plugin.h:396 [inline] RIP: 0010:__rcu_read_unlock+0x2a/0xe0 kernel/rcu/tree_plugin.h:435 Code: f3 0f 1e fa 41 57 41 56 41 55 41 54 53 49 bf 00 00 00 00 00 fc ff df 65 48 8b 3c 25 08 40 a0 92 48 8d 9f 44 04 00 00 49 89 dc <49> c1 ec 03 43 0f b6 04 3c 84 c0 75 4f ff 0b 75 1d 4c 8d b7 48 04 RSP: 0018:ffffc90000006c30 EFLAGS: 00000286 RAX: 50167c98cf70e600 RBX: ffff88802724de44 RCX: 50167c98cf70e600 RDX: 0000000000000004 RSI: ffffffff8dba5b5c RDI: ffff88802724da00 RBP: ffffc90000006d70 R08: ffffc90000006bd7 R09: 0000000000000000 R10: ffffc90000006bc0 R11: fffff52000000d7b R12: ffff88802724de44 R13: 00000000ffffffe4 R14: 0000000000000001 R15: dffffc0000000000 FS: 00007f7c505716c0(0000) GS:ffff888125c1c000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000001100 CR3: 000000007f1ca000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000200000000300 DR2: 0000200000000300 DR3: 0000200000000300 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: rcu_read_unlock include/linux/rcupdate.h:873 [inline] __perf_event_output kernel/events/core.c:8488 [inline] perf_event_output_forward+0x384/0x430 kernel/events/core.c:8497 __perf_event_overflow+0x7cf/0xe10 kernel/events/core.c:10372 perf_swevent_overflow kernel/events/core.c:10447 [inline] perf_swevent_event+0x2f4/0x5e0 kernel/events/core.c:-1 perf_tp_event+0x4f6/0x1380 kernel/events/core.c:10992 perf_trace_run_bpf_submit+0xee/0x170 kernel/events/core.c:10916 do_perf_trace_lock include/trace/events/lock.h:50 [inline] perf_trace_lock+0x2f8/0x3b0 include/trace/events/lock.h:50 __do_trace_lock_release include/trace/events/lock.h:69 [inline] trace_lock_release include/trace/events/lock.h:69 [inline] lock_release+0x3b2/0x3e0 kernel/locking/lockdep.c:5879 rcu_lock_release include/linux/rcupdate.h:341 [inline] rcu_read_unlock include/linux/rcupdate.h:871 [inline] class_rcu_destructor include/linux/rcupdate.h:1155 [inline] unwind_next_frame+0x19a9/0x2390 arch/x86/kernel/unwind_orc.c:680 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:243 [inline] __kasan_slab_free+0x5b/0x80 mm/kasan/common.c:275 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2417 [inline] slab_free mm/slub.c:4680 [inline] kmem_cache_free+0x18f/0x400 mm/slub.c:4782 kfree_skb_reason include/linux/skbuff.h:1275 [inline] kfree_skb include/linux/skbuff.h:1284 [inline] hsr_forward_skb+0x1ac6/0x2860 net/hsr/hsr_forward.c:-1 send_hsr_supervision_frame+0x612/0xb30 net/hsr/hsr_device.c:358 hsr_announce+0x1d5/0x360 net/hsr/hsr_device.c:415 call_timer_fn+0x17b/0x5f0 kernel/time/timer.c:1747 expire_timers kernel/time/timer.c:1798 [inline] __run_timers kernel/time/timer.c:2372 [inline] __run_timer_base+0x61a/0x860 kernel/time/timer.c:2384 run_timer_base kernel/time/timer.c:2393 [inline] run_timer_softirq+0xb7/0x180 kernel/time/timer.c:2403 handle_softirqs+0x283/0x870 kernel/softirq.c:579 __do_softirq kernel/softirq.c:613 [inline] invoke_softirq kernel/softirq.c:453 [inline] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1050 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:finish_task_switch+0x26b/0x950 kernel/sched/core.c:5225 Code: 0f 84 3c 01 00 00 48 85 db 0f 85 63 01 00 00 0f 1f 44 00 00 4c 8b 75 d0 4c 89 e7 e8 2f a7 ea 09 e8 5a 3f 36 00 fb 4c 8b 65 c0 <49> 8d bc 24 18 16 00 00 48 89 f8 48 c1 e8 03 42 0f b6 04 28 84 c0 RSP: 0018:ffffc900032277d8 EFLAGS: 00000286 RAX: 50167c98cf70e600 RBX: 0000000000000000 RCX: 50167c98cf70e600 RDX: 0000000000000000 RSI: ffffffff8d9b68b0 RDI: ffffffff8be33280 RBP: ffffc90003227830 R08: ffffffff8fa37e37 R09: 1ffffffff1f46fc6 R10: dffffc0000000000 R11: fffffbfff1f46fc7 R12: ffff88802724da00 R13: dffffc0000000000 R14: ffff888052113c00 R15: ffff8880b863ab58 context_switch kernel/sched/core.c:5360 [inline] __schedule+0x17a0/0x4cc0 kernel/sched/core.c:6961 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7288 irqentry_exit+0x6f/0x90 kernel/entry/common.c:197 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:its_return_thunk+0x0/0x10 arch/x86/lib/retpoline.S:412 Code: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 e9 ab 62 b7 f5 cc RSP: 0018:ffffc90003227bd8 EFLAGS: 00000297 RAX: ffffffff81b3d9d3 RBX: 0000000000000001 RCX: 0000000000000002 RDX: ffff88802724da00 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc90003227cf0 R08: ffff88807a2986c3 R09: 1ffff1100f4530d8 R10: dffffc0000000000 R11: ffffed100f4530d9 R12: 00000000000f4240 R13: 0000000000000000 R14: ffff88807a2986c0 R15: 00000000ffffffff futex_wake+0x1a3/0x560 kernel/futex/waitwake.c:175 do_futex+0x395/0x420 kernel/futex/syscalls.c:107 __do_sys_futex kernel/futex/syscalls.c:179 [inline] __se_sys_futex+0x36f/0x400 kernel/futex/syscalls.c:160 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f7c4f78ebe9 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:00007f7c505710e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: ffffffffffffffda RBX: 00007f7c4f9c5fa8 RCX: 00007f7c4f78ebe9 RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007f7c4f9c5fac RBP: 00007f7c4f9c5fa0 R08: 7fffffffffffffff R09: 0000000000000000 R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f7c4f9c6038 R14: 00007ffd4560d380 R15: 00007ffd4560d468 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 12042 Comm: kworker/u8:24 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline] RIP: 0010:smp_call_function_many_cond+0xd38/0x12d0 kernel/smp.c:877 Code: 89 ee 83 e6 01 31 ff e8 b6 62 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 61 5e 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 45 5e 0b 00 eb e4 44 RSP: 0018:ffffc900054b7660 EFLAGS: 00000293 RAX: 0000000000000000 RBX: 1ffff110170c8341 RCX: ffff88802bd6bc00 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc900054b77e0 R08: ffffffff8fa37e37 R09: 1ffffffff1f46fc6 R10: dffffc0000000000 R11: fffffbfff1f46fc7 R12: ffff8880b8641a08 R13: dffffc0000000000 R14: ffff8880b873b1c0 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff888125d1c000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fd1b8fc6038 CR3: 000000000df36000 CR4: 00000000003526f0 DR0: 0000200000000300 DR1: 0000200000000300 DR2: 0000200000000300 DR3: 0000200000000300 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1044 on_each_cpu include/linux/smp.h:71 [inline] smp_text_poke_sync_each_cpu arch/x86/kernel/alternative.c:2653 [inline] smp_text_poke_batch_finish+0x5f9/0x1130 arch/x86/kernel/alternative.c:2863 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146 static_key_enable_cpuslocked+0x128/0x250 kernel/jump_label.c:210 static_key_enable+0x1a/0x20 kernel/jump_label.c:223 toggle_allocation_gate+0xad/0x240 mm/kfence/core.c:850 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245