rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (1 GPs behind) idle=efd4/1/0x4000000000000000 softirq=280088/280089 fqs=6
rcu: 	(detected by 1, t=10502 jiffies, g=260401, q=890 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 7920 Comm: syz.1.7539 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
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 e9 53 91 11 74 11 83 e0 04 c1 e8 02 5b 41 5e 41 5f <e9> b2 34 65 ff cc e8 21 63 88 ff eb e8 48 c7 c7 00 01 96 8e 48 89
RSP: 0018:ffffc90000007d50 EFLAGS: 00000012
RAX: 0000000000000001 RBX: 0000000000000086 RCX: 0000000000010003
RDX: 0000000000000001 RSI: ffffffff8c293c80 RDI: ffffffff8c293c40
RBP: ffff8880822cc300 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff52000000f98 R12: ffff8880b86281c0
R13: ffffffff81b2cd19 R14: ffffffff9a6dfcd0 R15: ffff8880b8628450
FS:  00007f827b0656c0(0000) GS:ffff88812525a000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f827a1ea540 CR3: 000000005bbf5000 CR4: 0000000000350ef0
Call Trace:
 <IRQ>
 trace_lock_release include/trace/events/lock.h:68 [inline]
 lock_release+0x4b/0x3c0 kernel/locking/lockdep.c:5879
 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:176 [inline]
 _raw_spin_unlock_irqrestore+0x1b/0x80 kernel/locking/spinlock.c:198
 debug_hrtimer_deactivate kernel/time/hrtimer.c:490 [inline]
 __run_hrtimer kernel/time/hrtimer.c:2000 [inline]
 __hrtimer_run_queues+0x239/0xa10 kernel/time/hrtimer.c:2096
 hrtimer_interrupt+0x448/0x910 kernel/time/hrtimer.c:2215
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1051 [inline]
 __sysvec_apic_timer_interrupt+0x102/0x430 arch/x86/kernel/apic/apic.c:1068
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
 sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1062
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:sock_recvmsg_nosec+0x95/0x170 net/socket.c:-1
Code: 49 8d 7f 28 48 89 f8 48 c1 e8 03 80 3c 18 00 74 05 e8 2f 9d be f8 49 8b 57 28 4c 89 f7 4c 89 fe 41 89 ef 89 e9 e8 0b ea de 00 <89> c5 e8 f4 4a 36 f8 84 c0 74 61 e8 7b 73 51 f8 0f 1f 44 00 00 e8
RSP: 0018:ffffc900054a78a8 EFLAGS: 00000246
RAX: 0000000000000000 RBX: dffffc0000000000 RCX: 1b045914e8c65100
RDX: 0000000000000001 RSI: 0000000000000008 RDI: 00000000ffffffff
RBP: 0000000000000002 R08: ffffc900054a76a7 R09: 1ffff92000a94ed4
R10: dffffc0000000000 R11: fffff52000a94ed5 R12: ffffffff8a51dff0
R13: 0000000000000000 R14: ffff888087436d80 R15: 0000000000000002
 ____sys_recvmsg+0x3e3/0x4a0 net/socket.c:2902
 ___sys_recvmsg+0x213/0x5a0 net/socket.c:2946
 do_recvmmsg+0x31a/0x7f0 net/socket.c:3041
 __sys_recvmmsg net/socket.c:3115 [inline]
 __do_sys_recvmmsg net/socket.c:3138 [inline]
 __se_sys_recvmmsg net/socket.c:3131 [inline]
 __x64_sys_recvmmsg+0x198/0x250 net/socket.c:3131
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f827a19ce59
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:00007f827b065028 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: ffffffffffffffda RBX: 00007f827a416090 RCX: 00007f827a19ce59
RDX: 0000000000010106 RSI: 00002000000000c0 RDI: 0000000000000004
RBP: 00007f827a232e6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f827a416128 R14: 00007f827a416090 R15: 00007ffd436e3518
 </TASK>
rcu: rcu_preempt kthread starved for 10490 jiffies! g260401 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:27720 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5504 [inline]
 __schedule+0x17d9/0x56c0 kernel/sched/core.c:7228
 __schedule_loop kernel/sched/core.c:7307 [inline]
 schedule+0x164/0x360 kernel/sched/core.c:7322
 schedule_timeout+0x152/0x2c0 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x30c/0x11f0 kernel/rcu/tree.c:2123
 rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2325
 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: 1 UID: 0 PID: 2622 Comm: kworker/u8:21 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline]
RIP: 0010:smp_call_function_many_cond+0x10b0/0x14b0 kernel/smp.c:892
Code: c0 75 73 41 8b 1e 89 de 83 e6 01 31 ff e8 08 1f 0c 00 83 e3 01 48 bb 00 00 00 00 00 fc ff df 75 07 e8 b4 1a 0c 00 eb 37 f3 90 <41> 0f b6 04 1c 84 c0 75 10 41 f7 06 01 00 00 00 74 1e e8 99 1a 0c
RSP: 0018:ffffc900042ff720 EFLAGS: 00000293
RAX: ffffffff81ba19d7 RBX: dffffc0000000000 RCX: ffff888052659f00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc900042ff860 R08: ffffffff903189f7 R09: 1ffffffff206313e
R10: dffffc0000000000 R11: fffffbfff206313f R12: 1ffff110170c85c5
R13: ffff8880b873c2c8 R14: ffff8880b8642e28 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff88812535a000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa3a0d456b8 CR3: 000000000e746000 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:2773 [inline]
 smp_text_poke_batch_finish+0x5fd/0x1110 arch/x86/kernel/alternative.c:2983
 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:3322 [inline]
 process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3405
 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3486
 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>