rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (1 GPs behind) idle=d25c/1/0x4000000000000000 softirq=144517/144517 fqs=1
rcu: 	(detected by 0, t=10506 jiffies, g=144989, q=802 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 24589 Comm: syz.9.4797 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
RIP: 0010:__run_hrtimer kernel/time/hrtimer.c:1932 [inline]
RIP: 0010:__hrtimer_run_queues+0x3c3/0xa20 kernel/time/hrtimer.c:1994
Code: 00 00 00 fc ff df 42 0f b6 04 33 84 c0 0f 85 e2 02 00 00 41 c7 04 24 01 00 00 00 48 89 ef 4d 89 fb 2e e8 90 22 03 0a 41 89 c7 <42> 0f b6 04 33 84 c0 0f 85 dc 02 00 00 41 c7 04 24 00 00 00 00 4c
RSP: 0018:ffffc90000a08dd8 EFLAGS: 00000096
RAX: 0000000000000001 RBX: 1ffff11005218cf7 RCX: 0000000080010000
RDX: 0000000000000001 RSI: ffffffff8e23a932 RDI: ffff8880290c5c40
RBP: ffff888066b49300 R08: ffff888066b4919f R09: 1ffff1100cd69233
R10: dffffc0000000000 R11: ffffed100cd69234 R12: ffff8880290c67b8
R13: 1ffff110170e507a R14: dffffc0000000000 R15: 0000000000000001
FS:  00005555591ab500(0000) GS:ffff88812533d000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000001100 CR3: 00000000981f1000 CR4: 0000000000350ef0
Call Trace:
 <IRQ>
 hrtimer_interrupt+0x44b/0x950 kernel/time/hrtimer.c:2113
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
 __sysvec_apic_timer_interrupt+0x102/0x430 arch/x86/kernel/apic/apic.c:1067
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline]
 sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1061
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:rcu_is_watching+0x74/0xb0 kernel/rcu/tree.c:754
Code: 93 49 03 1e 48 89 d8 48 c1 e8 03 42 0f b6 04 38 84 c0 75 34 8b 03 65 ff 0d 09 f0 93 11 74 11 83 e0 04 c1 e8 02 5b 41 5e 41 5f <e9> d2 00 66 ff cc e8 31 7b 89 ff eb e8 48 c7 c7 00 30 96 8e 48 89
RSP: 0018:ffffc9000613f978 EFLAGS: 00000212
RAX: 0000000000000001 RBX: ffffffff81b7cfa2 RCX: 0000000080000001
RDX: 0000000000000000 RSI: ffffffff8c2829e0 RDI: ffffffff8c2829a0
RBP: 0000000000000000 R08: ffffffff81b7cfa2 R09: ffffffff8e95caa0
R10: dffffc0000000000 R11: fffffbfff2065937 R12: ffffc9000613fad0
R13: ffffffff81b7cfa2 R14: ffffffff8e95caa0 R15: 0000000000000000
 trace_lock_release include/trace/events/lock.h:69 [inline]
 lock_release+0x4b/0x3c0 kernel/locking/lockdep.c:5879
 rcu_lock_release include/linux/rcupdate.h:310 [inline]
 rcu_read_unlock include/linux/rcupdate.h:869 [inline]
 class_rcu_destructor include/linux/rcupdate.h:1181 [inline]
 futex_unqueue+0x20c/0x240 kernel/futex/core.c:964
 __futex_wait+0x24e/0x420 kernel/futex/waitwake.c:694
 futex_wait+0x121/0x390 kernel/futex/waitwake.c:719
 do_futex+0x333/0x420 kernel/futex/syscalls.c:130
 __do_sys_futex kernel/futex/syscalls.c:207 [inline]
 __se_sys_futex+0x3a8/0x450 kernel/futex/syscalls.c:188
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff6e779c819
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffcb25a9ff8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: ffffffffffffffda RBX: 00000000001b1edd RCX: 00007ff6e779c819
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007ff6e7a15fac
RBP: 0000000000000032 R08: 3fffffffffffffff R09: 0000000000000000
R10: 00007ffcb25aa100 R11: 0000000000000246 R12: 00007ffcb25aa120
R13: 00007ff6e7a15fac R14: 00000000001b1f0f R15: 00007ffcb25aa100
 </TASK>
rcu: rcu_preempt kthread starved for 10500 jiffies! g144989 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:27544 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5387 [inline]
 __schedule+0x17b4/0x5680 kernel/sched/core.c:7188
 __schedule_loop kernel/sched/core.c:7267 [inline]
 schedule+0x164/0x360 kernel/sched/core.c:7282
 schedule_timeout+0x158/0x2c0 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x312/0x11d0 kernel/rcu/tree.c:2095
 rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2297
 kthread+0x388/0x470 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 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: 0 UID: 0 PID: 36 Comm: kworker/u8:2 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline]
RIP: 0010:smp_call_function_many_cond+0xe37/0x1210 kernel/smp.c:892
Code: 89 ee 83 e6 01 31 ff e8 c7 fc 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 72 f8 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 56 f8 0b 00 eb e4 44
RSP: 0018:ffffc90000ac7700 EFLAGS: 00000293
RAX: 0000000000000000 RBX: 1ffff110170e8161 RCX: ffff8880202e3d80
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90000ac7840 R08: ffffffff9032c9b7 R09: 1ffffffff2065936
R10: dffffc0000000000 R11: fffffbfff2065937 R12: ffff8880b8740b08
R13: dffffc0000000000 R14: ffff8880b863c108 R15: 0000000000000001
FS:  0000000000000000(0000) GS:ffff88812523d000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007feb2661ed58 CR3: 000000000e74a000 CR4: 0000000000350ef0
Call Trace:
 <TASK>
 on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1057
 on_each_cpu include/linux/smp.h:72 [inline]
 smp_text_poke_sync_each_cpu arch/x86/kernel/alternative.c:2761 [inline]
 smp_text_poke_batch_finish+0x5f5/0x1160 arch/x86/kernel/alternative.c:2971
 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146
 static_key_enable_cpuslocked+0x128/0x240 kernel/jump_label.c:210
 static_key_enable+0x1a/0x20 kernel/jump_label.c:223
 toggle_allocation_gate+0xab/0x290 mm/kfence/core.c:906
 process_one_work kernel/workqueue.c:3302 [inline]
 process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3385
 worker_thread+0xa53/0xfc0 kernel/workqueue.c:3466
 kthread+0x388/0x470 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>