syzbot

watchdog: BUG: soft lockup - CPU#0 stuck for 144s! [syz.6.1022:9532]
Modules linked in:
irq event stamp: 7130837
hardirqs last  enabled at (7130836): [<ffffffff8b462c14>] irqentry_exit+0x74/0x90 kernel/entry/common.c:214
hardirqs last disabled at (7130837): [<ffffffff8b46184e>] sysvec_apic_timer_interrupt+0xe/0xc0 arch/x86/kernel/apic/apic.c:1052
softirqs last  enabled at (74): [<ffffffff8168f738>] local_bh_enable include/linux/bottom_half.h:33 [inline]
softirqs last  enabled at (74): [<ffffffff8168f738>] fpregs_unlock arch/x86/include/asm/fpu/api.h:77 [inline]
softirqs last  enabled at (74): [<ffffffff8168f738>] kernel_fpu_end+0xc8/0x120 arch/x86/kernel/fpu/core.c:479
softirqs last disabled at (473): [<ffffffff8184ccfa>] __do_softirq kernel/softirq.c:656 [inline]
softirqs last disabled at (473): [<ffffffff8184ccfa>] invoke_softirq kernel/softirq.c:496 [inline]
softirqs last disabled at (473): [<ffffffff8184ccfa>] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:723
CPU: 0 UID: 0 PID: 9532 Comm: syz.6.1022 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:lock_acquire+0x175/0x360 kernel/locking/lockdep.c:5872
Code: 00 00 00 00 9c 8f 44 24 30 f7 44 24 30 00 02 00 00 0f 85 cd 00 00 00 f7 44 24 08 00 02 00 00 74 01 fb 65 48 8b 05 fb cc d0 10 <48> 3b 44 24 58 0f 85 f2 00 00 00 48 83 c4 60 5b 41 5c 41 5d 41 5e
RSP: 0018:ffffc900000072f8 EFLAGS: 00000206
RAX: d46d2fac08d93a00 RBX: 0000000000000000 RCX: d46d2fac08d93a00
RDX: 0000000000000000 RSI: ffffffff8d8f29a6 RDI: ffffffff8bbf03e0
RBP: ffffffff81738d25 R08: 0000000000000000 R09: ffffffff81738d25
R10: ffffc900000074b8 R11: ffffffff81ac2cd0 R12: 0000000000000002
R13: ffffffff8df3d2e0 R14: 0000000000000000 R15: 0000000000000246
FS:  00007efdc04126c0(0000) GS:ffff88812613e000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000100000001 CR3: 0000000073dfe000 CR4: 00000000003526f0
DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 rcu_read_lock include/linux/rcupdate.h:867 [inline]
 class_rcu_constructor include/linux/rcupdate.h:1195 [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
 kasan_save_stack mm/kasan/common.c:56 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:77
 unpoison_slab_object mm/kasan/common.c:342 [inline]
 __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:368
 kasan_slab_alloc include/linux/kasan.h:252 [inline]
 slab_post_alloc_hook mm/slub.c:4962 [inline]
 slab_alloc_node mm/slub.c:5272 [inline]
 kmem_cache_alloc_node_noprof+0x433/0x710 mm/slub.c:5324
 __alloc_skb+0x112/0x2d0 net/core/skbuff.c:660
 alloc_skb include/linux/skbuff.h:1383 [inline]
 nlmsg_new include/net/netlink.h:1055 [inline]
 xfrm_exp_policy_notify net/xfrm/xfrm_user.c:3956 [inline]
 xfrm_send_policy_notify+0x5e4/0x1bb0 net/xfrm/xfrm_user.c:4076
 km_policy_notify+0x121/0x200 net/xfrm/xfrm_state.c:2731
 km_policy_expired+0xb8/0x100 net/xfrm/xfrm_state.c:2821
 xfrm_policy_timer+0x364/0x630 net/xfrm/xfrm_policy.c:420
 call_timer_fn+0x17e/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+0x286/0x870 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:723
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1052 [inline]
 sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1052
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:generic_exec_single+0x481/0x500 kernel/smp.c:453
Code: 75 11 e8 b2 7f 0b 00 48 85 db 75 16 e8 a8 7f 0b 00 eb 15 e8 a1 7f 0b 00 e8 bc 9d 91 09 48 85 db 74 ea e8 92 7f 0b 00 fb 31 c0 <48> c7 44 24 20 0e 36 e0 45 4b c7 04 2c 00 00 00 00 66 43 c7 44 2c
RSP: 0018:ffffc900055d79c0 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 0000000000000200 RCX: 0000000000080000
RDX: ffffc9000c792000 RSI: 0000000000000543 RDI: 0000000000000544
RBP: ffffc900055d7a90 R08: ffffffff8f7cd177 R09: 1ffffffff1ef9a2e
R10: dffffc0000000000 R11: fffffbfff1ef9a2f R12: 1ffff92000abaf3c
R13: dffffc0000000000 R14: 0000000000000000 R15: 1ffff92000abaf5d
 smp_call_function_single+0x351/0x590 kernel/smp.c:684
 task_function_call kernel/events/core.c:121 [inline]
 perf_install_in_context+0x593/0x8f0 kernel/events/core.c:3107
 __do_sys_perf_event_open kernel/events/core.c:13735 [inline]
 __se_sys_perf_event_open+0x193a/0x1d70 kernel/events/core.c:13377
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7efdbf58efc9
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:00007efdc0412038 EFLAGS: 00000246 ORIG_RAX: 000000000000012a
RAX: ffffffffffffffda RBX: 00007efdbf7e6090 RCX: 00007efdbf58efc9
RDX: ffffffffffffffff RSI: 0000000000000000 RDI: 00002000000003c0
RBP: 00007efdbf611f91 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000
R13: 00007efdbf7e6128 R14: 00007efdbf7e6090 R15: 00007ffe42726678
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 60 Comm: kworker/u8:4 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
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 96 73 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 41 6f 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 25 6f
RSP: 0018:ffffc9000211f640 EFLAGS: 00000293
RAX: ffffffff81b494cb RBX: 1ffff11017108431 RCX: ffff88801bfb5ac0
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc9000211f7c0 R08: ffffffff8f7cd177 R09: 1ffffffff1ef9a2e
R10: dffffc0000000000 R11: fffffbfff1ef9a2f R12: ffff8880b8842188
R13: dffffc0000000000 R14: ffff8880b893b1c0 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff88812623e000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f7659d15000 CR3: 000000000dd38000 CR4: 00000000003526f0
DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <TASK>
 on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1043
 on_each_cpu include/linux/smp.h:71 [inline]
 smp_text_poke_sync_each_cpu arch/x86/kernel/alternative.c:2713 [inline]
 smp_text_poke_batch_finish+0x5f9/0x1130 arch/x86/kernel/alternative.c:2923
 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:852
 process_one_work kernel/workqueue.c:3263 [inline]
 process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346
 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>