rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (1 GPs behind) idle=1414/1/0x4000000000000000 softirq=40208/40210 fqs=0
rcu: 	(detected by 1, t=10505 jiffies, g=30153, q=262 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 6874 Comm: syz-executor Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:rb_erase+0x477/0xe60 lib/rbtree.c:444
Code: 89 ef e8 7c 51 e4 f6 4d 89 7d 00 45 31 ed 4c 89 e0 48 c1 e8 03 80 3c 28 00 74 08 4c 89 e7 e8 60 51 e4 f6 4d 89 34 24 4d 85 ed <0f> 84 c1 09 00 00 31 db 48 8b 44 24 18 48 c1 e8 03 48 89 44 24 10
RSP: 0018:ffffc90000007ca8 EFLAGS: 00000046
RAX: 1ffff11017104f82 RBX: ffff8880b8827c10 RCX: dffffc0000000000
RDX: 0000000000010000 RSI: ffff8880b8827c10 RDI: ffff8880290a2348
RBP: dffffc0000000000 R08: ffffffff8f7cd477 R09: 1ffffffff1ef9a8e
R10: dffffc0000000000 R11: fffffbfff1ef9a8f R12: ffff8880290a2340
R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000000
FS:  000055555fed3500(0000) GS:ffff88812613e000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c2c200b CR3: 000000005e9cf000 CR4: 0000000000350ef0
Call Trace:
 <IRQ>
 rb_erase_cached include/linux/rbtree.h:126 [inline]
 timerqueue_del+0xae/0x100 lib/timerqueue.c:57
 __remove_hrtimer kernel/time/hrtimer.c:1114 [inline]
 __run_hrtimer kernel/time/hrtimer.c:1757 [inline]
 __hrtimer_run_queues+0x364/0xc60 kernel/time/hrtimer.c:1841
 hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1903
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1041 [inline]
 __sysvec_apic_timer_interrupt+0x10b/0x410 arch/x86/kernel/apic/apic.c:1058
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1052 [inline]
 sysvec_apic_timer_interrupt+0xa1/0xc0 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:__sanitizer_cov_trace_pc+0x0/0x70 kernel/kcov.c:210
Code: 89 fb e8 23 00 00 00 48 8b 3d a4 c1 d2 0b 48 89 de 5b e9 93 86 5a 00 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <f3> 0f 1e fa 48 8b 04 24 65 48 8b 0c 25 08 20 6e 92 65 8b 15 a8 1b
RSP: 0018:ffffc90004db7b48 EFLAGS: 00000286
RAX: dffffc0000000000 RBX: ffffc90004db7d80 RCX: 0000000000000001
RDX: 000000000000c350 RSI: 0000000000989680 RDI: ffffc90004db7d40
RBP: 0000000000000001 R08: ffff888024b03c9b R09: 1ffff11004960793
R10: dffffc0000000000 R11: ffffed1004960794 R12: dffffc0000000000
R13: ffffc90004db7d40 R14: ffffc90004db7d60 R15: 0000000000989680
 hrtimer_start_range_ns+0x2e/0x1080 kernel/time/hrtimer.c:1306
 hrtimer_start_expires include/linux/hrtimer.h:273 [inline]
 hrtimer_sleeper_start_expires kernel/time/hrtimer.c:2039 [inline]
 do_nanosleep+0x18c/0x610 kernel/time/hrtimer.c:2113
 hrtimer_nanosleep+0x169/0x360 kernel/time/hrtimer.c:2163
 __do_sys_clock_nanosleep kernel/time/posix-timers.c:1398 [inline]
 __se_sys_clock_nanosleep+0x339/0x390 kernel/time/posix-timers.c:1375
 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: 0033:0x7f3ad55c1885
Code: 24 0c 89 3c 24 48 89 4c 24 18 e8 f6 54 ff ff 4c 8b 54 24 18 48 8b 54 24 10 41 89 c0 8b 74 24 0c 8b 3c 24 b8 e6 00 00 00 0f 05 <44> 89 c7 48 89 04 24 e8 4f 55 ff ff 48 8b 04 24 48 83 c4 28 f7 d8
RSP: 002b:00007ffeab7cb040 EFLAGS: 00000293 ORIG_RAX: 00000000000000e6
RAX: ffffffffffffffda RBX: 00000000000000d8 RCX: 00007f3ad55c1885
RDX: 00007ffeab7cb080 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007ffeab7cb0ec R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000001388
R13: 00000000000927c0 R14: 000000000005cd3d R15: 00007ffeab7cb140
 </TASK>
rcu: rcu_preempt kthread starved for 10505 jiffies! g30153 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
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:26464 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5325 [inline]
 __schedule+0x1798/0x4cc0 kernel/sched/core.c:6929
 __schedule_loop kernel/sched/core.c:7011 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:7026
 schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2083
 rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2285
 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>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 UID: 0 PID: 12 Comm: kworker/u8:0 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+0xd38/0x12d0 kernel/smp.c:877
Code: 89 ee 83 e6 01 31 ff e8 b6 73 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 61 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 45 6f 0b 00 eb e4 44
RSP: 0018:ffffc90000117640 EFLAGS: 00000293
RAX: 0000000000000000 RBX: 1ffff11017108441 RCX: ffff88801c6bdac0
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc900001177c0 R08: ffffffff8f7cd477 R09: 1ffffffff1ef9a8e
R10: dffffc0000000000 R11: fffffbfff1ef9a8f R12: ffff8880b8842208
R13: dffffc0000000000 R14: ffff8880b893b240 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff88812623e000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005555936b45c8 CR3: 000000000dd38000 CR4: 0000000000350ef0
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>