syzbot

watchdog: BUG: soft lockup - CPU#0 stuck for 123s! [syz.5.1531:12031]
Modules linked in:
irq event stamp: 10780969
hardirqs last  enabled at (10780968): [<ffffffff8b7ad234>] irqentry_exit+0x74/0x90 kernel/entry/common.c:200
hardirqs last disabled at (10780969): [<ffffffff8b7abe6e>] sysvec_apic_timer_interrupt+0xe/0xc0 arch/x86/kernel/apic/apic.c:1050
softirqs last  enabled at (1094112): [<ffffffff8185070a>] __do_softirq kernel/softirq.c:613 [inline]
softirqs last  enabled at (1094112): [<ffffffff8185070a>] invoke_softirq kernel/softirq.c:453 [inline]
softirqs last  enabled at (1094112): [<ffffffff8185070a>] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680
softirqs last disabled at (1094115): [<ffffffff8185070a>] __do_softirq kernel/softirq.c:613 [inline]
softirqs last disabled at (1094115): [<ffffffff8185070a>] invoke_softirq kernel/softirq.c:453 [inline]
softirqs last disabled at (1094115): [<ffffffff8185070a>] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680
CPU: 0 UID: 0 PID: 12031 Comm: syz.5.1531 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:bpf_prog_array_valid include/linux/trace_events.h:452 [inline]
RIP: 0010:do_perf_trace_lock include/trace/events/lock.h:50 [inline]
RIP: 0010:perf_trace_lock+0x132/0x3b0 include/trace/events/lock.h:50
Code: 3c 38 00 74 08 48 89 df e8 7b f5 86 00 4c 89 74 24 38 49 83 c6 68 4c 89 f0 48 c1 e8 03 48 8b 4c 24 10 48 03 0b 48 89 4c 24 10 <42> 80 3c 38 00 74 08 4c 89 f7 e8 4f f5 86 00 49 83 3e 00 75 25 48
RSP: 0018:ffffc90000007420 EFLAGS: 00000282
RAX: 1ffffffff1c0124d RBX: ffffffff8dbe2d10 RCX: ffffe8ffffc23158
RDX: ffffffff8172d195 RSI: ffffffff8be34260 RDI: ffffffff8be34220
RBP: ffffc90000007520 R08: ffffc90005797f48 R09: 0000000000000000
R10: ffffc900000076b8 R11: fffff52000000ed9 R12: 1ffff92000000e8c
R13: 000000000000000d R14: ffffffff8e009268 R15: dffffc0000000000
FS:  00007f49ba5856c0(0000) GS:ffff888125c12000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc79dd056c0 CR3: 0000000076cdc000 CR4: 00000000003526f0
DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 __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:1169 [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:2422 [inline]
 slab_free mm/slub.c:4695 [inline]
 kmem_cache_free+0x18f/0x400 mm/slub.c:4797
 kfree_skb_reason include/linux/skbuff.h:1275 [inline]
 inet_frag_rbtree_purge net/ipv4/inet_fragment.c:281 [inline]
 inet_frag_destroy+0x17b/0x2a0 net/ipv4/inet_fragment.c:305
 inet_frag_putn include/net/inet_frag.h:151 [inline]
 ip_expire+0x5b5/0x8f0 net/ipv4/ip_fragment.c:191
 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
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:strlen+0x5d/0x70 lib/string.c:422
Code: ff c3 49 8d 47 01 42 80 7c 3f 01 00 75 de eb 19 89 d9 80 e1 07 38 c1 7c e6 49 89 fc 48 89 df e8 69 07 ad f6 4c 89 e7 eb d6 5b <41> 5c 41 5e 41 5f e9 18 00 07 00 cc 0f 1f 80 00 00 00 00 90 90 90
RSP: 0018:ffffc90005797420 EFLAGS: 00000246
RAX: 000000000000000d RBX: ffffffff8e13a138 RCX: 000000008b8bd505
RDX: 0000000000000000 RSI: ffffffff8e13a120 RDI: ffffffff8b8bd560
RBP: ffffc90005797538 R08: 0000000000000002 R09: 0000000000000000
R10: ffffc90005797208 R11: ffffffff81ac4d00 R12: 1ffff92000af2e90
R13: ffffffff8e13a120 R14: dffffc0000000000 R15: 000000000000000c
 __fortify_strlen include/linux/fortify-string.h:268 [inline]
 trace_event_get_offsets_lock_acquire include/trace/events/lock.h:24 [inline]
 do_perf_trace_lock_acquire include/trace/events/lock.h:24 [inline]
 perf_trace_lock_acquire+0xcb/0x410 include/trace/events/lock.h:24
 __do_trace_lock_acquire include/trace/events/lock.h:24 [inline]
 trace_lock_acquire include/trace/events/lock.h:24 [inline]
 lock_acquire+0x311/0x360 kernel/locking/lockdep.c:5831
 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
 __slab_free+0x303/0x3c0 mm/slub.c:4606
 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:4191 [inline]
 slab_alloc_node mm/slub.c:4240 [inline]
 kmem_cache_alloc_lru_noprof+0x1c6/0x3d0 mm/slub.c:4259
 __d_alloc+0x36/0x7a0 fs/dcache.c:1690
 d_alloc_pseudo+0x21/0xc0 fs/dcache.c:1821
 alloc_path_pseudo fs/file_table.c:363 [inline]
 alloc_file_pseudo+0xcc/0x210 fs/file_table.c:379
 __anon_inode_getfile fs/anon_inodes.c:166 [inline]
 anon_inode_getfile+0xc5/0x1a0 fs/anon_inodes.c:204
 __do_sys_perf_event_open kernel/events/core.c:13658 [inline]
 __se_sys_perf_event_open+0xf20/0x1d70 kernel/events/core.c:13360
 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: 0033:0x7f49b978ec29
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:00007f49ba585038 EFLAGS: 00000246 ORIG_RAX: 000000000000012a
RAX: ffffffffffffffda RBX: 00007f49b99d5fa0 RCX: 00007f49b978ec29
RDX: ffffffffffffffff RSI: 0000000000000000 RDI: 0000200000000040
RBP: 00007f49b9811e41 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000
R13: 00007f49b99d6038 R14: 00007f49b99d5fa0 R15: 00007ffff26f0bc8
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 6261 Comm: kworker/u8:10 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
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 63 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 61 5f 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 5f 0b 00 eb e4 44
RSP: 0018:ffffc9000c577660 EFLAGS: 00000293
RAX: 0000000000000000 RBX: 1ffff110170c8341 RCX: ffff88802d885a00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc9000c5777e0 R08: ffffffff8fa3b237 R09: 1ffffffff1f47646
R10: dffffc0000000000 R11: fffffbfff1f47647 R12: ffff8880b8641a08
R13: dffffc0000000000 R14: ffff8880b873b1c0 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff888125d12000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f18a7bd6038 CR3: 000000000df36000 CR4: 00000000003526f0
DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff1 DR7: 0000000000000600
Call Trace:
 <TASK>
 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_disable_cpuslocked+0xc5/0x1b0 kernel/jump_label.c:240
 static_key_disable+0x1a/0x20 kernel/jump_label.c:248
 toggle_allocation_gate+0x1a1/0x240 mm/kfence/core.c:855
 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+0x70e/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x436/0x7d0 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>