rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (1 GPs behind) idle=9eac/1/0x4000000000000000 softirq=33695/33698 fqs=0
rcu: 	(detected by 0, t=10506 jiffies, g=28473, q=85 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 8819 Comm: syz-executor Not tainted 6.15.0-rc4-syzkaller-00296-ge8ab83e34bdc #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/29/2025
RIP: 0010:rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline]
RIP: 0010:rcu_is_watching+0x17/0xb0 kernel/rcu/tree.c:736
Code: 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 41 57 41 56 53 65 ff 05 a0 68 ce 10 e8 fb 49 af 09 89 c3 <83> f8 08 73 65 49 bf 00 00 00 00 00 fc ff df 4c 8d 34 dd 10 dc 96
RSP: 0018:ffffc90000a08cf8 EFLAGS: 00000082
RAX: 0000000000000001 RBX: 0000000000000001 RCX: d07a038229c90b00
RDX: ffff88802033da00 RSI: ffffffff8bc1d200 RDI: ffffffff8bc1d1c0
RBP: ffffc90000a08e90 R08: ffffffff8f7ed977 R09: 1ffffffff1efdb2e
R10: dffffc0000000000 R11: fffffbfff1efdb2f R12: ffff88802fefa340
R13: dffffc0000000000 R14: 0000000000000001 R15: ffff8880b89277c0
FS:  000055557fecd500(0000) GS:ffff8881261cb000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f08b6718310 CR3: 000000003025b000 CR4: 0000000000350ef0
Call Trace:
 <IRQ>
 trace_hrtimer_cancel include/trace/events/timer.h:317 [inline]
 debug_deactivate+0x80/0x200 kernel/time/hrtimer.c:491
 __run_hrtimer kernel/time/hrtimer.c:1729 [inline]
 __hrtimer_run_queues+0x2b0/0xc60 kernel/time/hrtimer.c:1825
 hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1887
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline]
 __sysvec_apic_timer_interrupt+0x10b/0x410 arch/x86/kernel/apic/apic.c:1055
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline]
 sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1049
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0xa8/0x110 kernel/locking/spinlock.c:194
Code: 74 05 e8 0b a3 6e f6 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f6 44 24 21 02 75 4f f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 <e8> f3 24 38 f6 65 8b 05 5c b5 1c 07 85 c0 74 40 48 c7 04 24 0e 36
RSP: 0018:ffffc9001ddd7c80 EFLAGS: 00000206
RAX: d07a038229c90b00 RBX: 0000000000000216 RCX: d07a038229c90b00
RDX: 0000000000000000 RSI: ffffffff8d74aa91 RDI: 0000000000000001
RBP: ffffc9001ddd7d00 R08: ffffffff8f7ed977 R09: 1ffffffff1efdb2e
R10: dffffc0000000000 R11: fffffbfff1efdb2f R12: dffffc0000000000
R13: ffff88807dfa5400 R14: ffffffff999de150 R15: 1ffff92003bbaf90
 __debug_check_no_obj_freed lib/debugobjects.c:1108 [inline]
 debug_check_no_obj_freed+0x451/0x470 lib/debugobjects.c:1129
 slab_free_hook mm/slub.c:2311 [inline]
 slab_free mm/slub.c:4642 [inline]
 kmem_cache_free+0x116/0x3f0 mm/slub.c:4744
 do_symlinkat+0x3a7/0x3f0 fs/namei.c:4758
 __do_sys_symlinkat fs/namei.c:4765 [inline]
 __se_sys_symlinkat fs/namei.c:4762 [inline]
 __x64_sys_symlinkat+0x95/0xb0 fs/namei.c:4762
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f08b678dee7
Code: 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 0a 01 00 00 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:00007fff43f1fd98 EFLAGS: 00000206 ORIG_RAX: 000000000000010a
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f08b678dee7
RDX: 00007f08b68122fd RSI: 00000000ffffff9c RDI: 00007f08b6810e74
RBP: 00007fff43f1fddc R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000067
R13: 00000000000927c0 R14: 000000000005deda R15: 00007fff43f1fe30
 </TASK>
rcu: rcu_preempt kthread starved for 10506 jiffies! g28473 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0
rcu: 	Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt     state:R  running task     stack:27032 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5382 [inline]
 __schedule+0x16e2/0x4cd0 kernel/sched/core.c:6767
 __schedule_loop kernel/sched/core.c:6845 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:6860
 schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2046
 rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2248
 kthread+0x711/0x8a0 kernel/kthread.c:464
 ret_from_fork+0x4e/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 UID: 0 PID: 62 Comm: kworker/u8:4 Not tainted 6.15.0-rc4-syzkaller-00296-ge8ab83e34bdc #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/29/2025
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline]
RIP: 0010:smp_call_function_many_cond+0xe6e/0x11c0 kernel/smp.c:885
Code: 89 ee 83 e6 01 31 ff e8 20 6d 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 cb 68 0b 00 eb 37 f3 90 43 0f b6 04 2c <84> c0 75 10 41 f7 07 01 00 00 00 74 1e e8 b0 68 0b 00 eb e5 44 89
RSP: 0018:ffffc90001547700 EFLAGS: 00000293
RAX: 0000000000000000 RBX: ffff8880b883ad40 RCX: ffff88801ab81e00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90001547860 R08: ffffffff8f7ed977 R09: 1ffffffff1efdb2e
R10: dffffc0000000000 R11: fffffbfff1efdb2f R12: 1ffff11017127e99
R13: dffffc0000000000 R14: 0000000000000001 R15: ffff8880b893f4c8
FS:  0000000000000000(0000) GS:ffff8881260cb000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2ff01ff8 CR3: 000000000dd36000 CR4: 0000000000350ef0
Call Trace:
 <TASK>
 on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1052
 on_each_cpu include/linux/smp.h:71 [inline]
 text_poke_sync arch/x86/kernel/alternative.c:2455 [inline]
 text_poke_bp_batch+0x61a/0x940 arch/x86/kernel/alternative.c:2727
 text_poke_flush arch/x86/kernel/alternative.c:2856 [inline]
 text_poke_finish+0x30/0x50 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:3238 [inline]
 process_scheduled_works+0xade/0x17a0 kernel/workqueue.c:3319
 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400
 kthread+0x711/0x8a0 kernel/kthread.c:464
 ret_from_fork+0x4e/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>