watchdog: BUG: soft lockup - CPU#1 stuck for 143s! [syz.1.52:6197] Modules linked in: irq event stamp: 14874033 hardirqs last enabled at (14874032): [] irqentry_exit+0x74/0x90 kernel/entry/common.c:200 hardirqs last disabled at (14874033): [] sysvec_apic_timer_interrupt+0xe/0xc0 arch/x86/kernel/apic/apic.c:1050 softirqs last enabled at (14556840): [] __do_softirq kernel/softirq.c:613 [inline] softirqs last enabled at (14556840): [] invoke_softirq kernel/softirq.c:453 [inline] softirqs last enabled at (14556840): [] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680 softirqs last disabled at (14556843): [] __do_softirq kernel/softirq.c:613 [inline] softirqs last disabled at (14556843): [] invoke_softirq kernel/softirq.c:453 [inline] softirqs last disabled at (14556843): [] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680 CPU: 1 UID: 0 PID: 6197 Comm: syz.1.52 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_enter kernel/rcu/tree_plugin.h:391 [inline] RIP: 0010:__rcu_read_lock+0x2a/0x60 kernel/rcu/tree_plugin.h:414 Code: f3 0f 1e fa 53 65 48 8b 1c 25 08 40 a0 92 48 81 c3 44 04 00 00 48 89 d8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df 0f b6 04 08 <84> c0 75 18 ff 03 8b 03 3d 00 00 00 40 7d 07 5b e9 01 05 d5 09 cc RSP: 0018:ffffc90000a08508 EFLAGS: 00000a07 RAX: 0000000000000000 RBX: ffff88802d310444 RCX: dffffc0000000000 RDX: dffffc0000000000 RSI: ffffffff847e7c03 RDI: ffffc90000a085e8 RBP: dffffc0000000000 R08: ffffc90000a086b0 R09: 0000000000000020 R10: ffffc90000a08638 R11: ffffffff81ac3930 R12: 1ffff920001410bd R13: ffffc90000a08620 R14: ffffc90000a085e8 R15: ffffc900051675a0 FS: 00007fc9b49316c0(0000) GS:ffff888125d1c000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fc9b158fd58 CR3: 000000002eefc000 CR4: 00000000003526f0 Call Trace: rcu_read_lock include/linux/rcupdate.h:839 [inline] class_rcu_constructor include/linux/rcupdate.h:1169 [inline] unwind_next_frame+0x9e/0x2390 arch/x86/kernel/unwind_orc.c:479 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 unpoison_slab_object mm/kasan/common.c:330 [inline] __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:356 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4180 [inline] slab_alloc_node mm/slub.c:4229 [inline] kmem_cache_alloc_node_noprof+0x1bb/0x3c0 mm/slub.c:4281 __alloc_skb+0x112/0x2d0 net/core/skbuff.c:659 alloc_skb include/linux/skbuff.h:1336 [inline] ndisc_alloc_skb+0x9f/0x480 net/ipv6/ndisc.c:420 ndisc_send_rs+0x2b5/0x630 net/ipv6/ndisc.c:706 addrconf_rs_timer+0x369/0x670 net/ipv6/addrconf.c:4037 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:preempt_schedule_irq+0xb0/0x150 kernel/sched/core.c:7288 Code: 24 20 f6 44 24 21 02 74 0c 90 0f 0b 48 f7 03 08 00 00 00 74 64 bf 01 00 00 00 e8 fb 98 15 f6 e8 36 f3 4c f6 fb bf 01 00 00 00 5b ab ff ff 48 c7 44 24 40 00 00 00 00 9c 8f 44 24 40 8b 44 24 RSP: 0018:ffffc90005166d80 EFLAGS: 00000282 RAX: b4b95f17c8db8f00 RBX: 0000000000000000 RCX: b4b95f17c8db8f00 RDX: 0000000000000007 RSI: ffffffff8d9b6a5f RDI: 0000000000000001 RBP: ffffc90005166e30 R08: ffffffff8fa38037 R09: 1ffffffff1f47006 R10: dffffc0000000000 R11: fffffbfff1f47007 R12: 0000000000000000 R13: 0000000000000000 R14: dffffc0000000000 R15: 1ffff92000a2cdb0 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:__preempt_count_dec_and_test arch/x86/include/asm/preempt.h:-1 [inline] RIP: 0010:class_preempt_notrace_destructor include/linux/preempt.h:473 [inline] RIP: 0010:__do_trace_lock_acquire include/trace/events/lock.h:24 [inline] RIP: 0010:trace_lock_acquire include/trace/events/lock.h:24 [inline] RIP: 0010:lock_acquire+0x337/0x360 kernel/locking/lockdep.c:5831 Code: 8f 43 ff ff 48 83 c4 10 65 ff 0d b4 e1 02 11 8b 5c 24 08 4c 8b 74 24 10 4c 8b 7c 24 28 4c 8b 64 24 20 48 8b ac 24 98 00 00 00 <4c> 8b 6c 24 18 0f 85 fc fc ff ff e8 89 68 96 ff e9 f2 fc ff ff 90 RSP: 0018:ffffc90005166ef8 EFLAGS: 00000246 RAX: b4b95f17c8db8f00 RBX: 0000000000000000 RCX: 0000000000000000 RDX: ffffc9000c329000 RSI: 000000000000475c RDI: 000000000000475d RBP: ffffffff8172c195 R08: ffffc90005166b97 R09: 0000000000000000 R10: ffffc90005166b88 R11: fffff52000a2cd73 R12: 0000000000000002 R13: ffffffff8e139ea0 R14: 0000000000000000 R15: 0000000000000000 rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:841 [inline] class_rcu_constructor include/linux/rcupdate.h:1169 [inline] unwind_next_frame+0xc2/0x2390 arch/x86/kernel/unwind_orc.c:479 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 save_stack+0xf5/0x1f0 mm/page_owner.c:156 __reset_page_owner+0x71/0x1f0 mm/page_owner.c:308 reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1395 [inline] __free_frozen_pages+0xbc4/0xd30 mm/page_alloc.c:2895 discard_slab mm/slub.c:2753 [inline] __put_partials+0x156/0x1a0 mm/slub.c:3218 put_cpu_partial+0x17c/0x250 mm/slub.c:3293 __slab_free+0x2d5/0x3c0 mm/slub.c:4550 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x97/0x140 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:340 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4180 [inline] slab_alloc_node mm/slub.c:4229 [inline] __do_kmalloc_node mm/slub.c:4364 [inline] __kmalloc_noprof+0x224/0x4f0 mm/slub.c:4377 kmalloc_noprof include/linux/slab.h:909 [inline] tomoyo_realpath_from_path+0xe3/0x5d0 security/tomoyo/realpath.c:251 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_check_open_permission+0x1c1/0x3b0 security/tomoyo/file.c:771 security_file_open+0xb1/0x270 security/security.c:3144 do_dentry_open+0x384/0x13f0 fs/open.c:942 vfs_open+0x3b/0x340 fs/open.c:1095 do_open fs/namei.c:3887 [inline] path_openat+0x2ee5/0x3830 fs/namei.c:4046 do_filp_open+0x1fa/0x410 fs/namei.c:4073 do_sys_openat2+0x121/0x1c0 fs/open.c:1435 do_sys_open fs/open.c:1450 [inline] __do_sys_openat fs/open.c:1466 [inline] __se_sys_openat fs/open.c:1461 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1461 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: 0033:0x7fc9b3b8ebe9 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:00007fc9b4931038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007fc9b3dc5fa0 RCX: 00007fc9b3b8ebe9 RDX: 00000000000026e1 RSI: 00002000000002c0 RDI: ffffffffffffff9c RBP: 00007fc9b3c11e19 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fc9b3dc6038 R14: 00007fc9b3dc5fa0 R15: 00007fff678d6fe8 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 3517 Comm: kworker/u8:8 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+0xd33/0x12d0 kernel/smp.c:877 Code: 45 8b 2c 24 44 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 RSP: 0018:ffffc9000c327660 EFLAGS: 00000293 RAX: ffffffff81b44e0b RBX: 1ffff110170e7f61 RCX: ffff888030218000 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc9000c3277e0 R08: ffffffff8fa38037 R09: 1ffffffff1f47006 R10: dffffc0000000000 R11: fffffbfff1f47007 R12: ffff8880b873fb08 R13: dffffc0000000000 R14: ffff8880b863b1c0 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff888125c1c000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fe640ce6380 CR3: 000000000df36000 CR4: 00000000003526f0 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