rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (5 ticks this GP) idle=d854/1/0x4000000000000000 softirq=69508/69508 fqs=4
rcu: 	(detected by 1, t=10506 jiffies, g=85901, q=185 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 15584 Comm: syz.3.2395 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/06/2026
RIP: 0010:find_held_lock kernel/locking/lockdep.c:-1 [inline]
RIP: 0010:__lock_release kernel/locking/lockdep.c:5465 [inline]
RIP: 0010:lock_release+0x207/0x8c0 kernel/locking/lockdep.c:5810
Code: 89 44 24 30 83 f8 32 0f 83 d3 04 00 00 4b 8d 04 b6 4c 8d 24 c3 48 89 c3 4c 89 e7 48 8b 74 24 18 e8 1e 84 2e 09 44 89 7c 24 3c <44> 89 fa 85 c0 0f 84 d7 01 00 00 4d 85 e4 0f 84 01 03 00 00 4d 8d
RSP: 0018:ffffc90000007b60 EFLAGS: 00000046
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 99c8fbc490c24300
RDX: 1ffff11004785c9c RSI: ffff88807c57d300 RDI: ffff888023c2e4e8
RBP: ffffc90000007c78 R08: ffffffff8f8dda6f R09: 1ffffffff1f1bb4d
R10: dffffc0000000000 R11: fffffbfff1f1bb4e R12: ffff888023c2e4e8
R13: dffffc0000000000 R14: 0000000000000000 R15: 0000000000000000
FS:  00007f11ff6c16c0(0000) GS:ffff8880b8c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f11fe7f06e0 CR3: 000000005ddb7000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000008000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 __raw_spin_unlock include/linux/spinlock_api_smp.h:141 [inline]
 _raw_spin_unlock+0x16/0x40 kernel/locking/spinlock.c:186
 spin_unlock include/linux/spinlock.h:391 [inline]
 advance_sched+0x989/0xc70 net/sched/sch_taprio.c:998
 __run_hrtimer kernel/time/hrtimer.c:1754 [inline]
 __hrtimer_run_queues+0x525/0xc10 kernel/time/hrtimer.c:1818
 hrtimer_interrupt+0x39d/0x980 kernel/time/hrtimer.c:1880
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1077 [inline]
 __sysvec_apic_timer_interrupt+0xfb/0x3b0 arch/x86/kernel/apic/apic.c:1094
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline]
 sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1088
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:lock_release+0x594/0x8c0 kernel/locking/lockdep.c:5814
Code: 00 00 00 f7 84 24 80 00 00 00 00 02 00 00 43 c6 44 2f 04 f8 75 70 f7 44 24 50 00 02 00 00 74 01 fb 48 c7 44 24 60 0e 36 e0 45 <4b> c7 04 2f 00 00 00 00 43 c7 44 2f 08 00 00 00 00 65 48 8b 04 25
RSP: 0018:ffffc900035e7b60 EFLAGS: 00000206
RAX: 0000000000000001 RBX: ffffffffffffffff RCX: 99c8fbc490c24300
RDX: 0000000000000000 RSI: ffffffff8aeae2c0 RDI: ffffffff8b3c5260
RBP: ffffc900035e7c70 R08: ffffffff8f8dda6f R09: 1ffffffff1f1bb4d
R10: dffffc0000000000 R11: fffffbfff1f1bb4e R12: ffff888023c2e4e8
R13: dffffc0000000000 R14: ffff888023c2e4d8 R15: 1ffff920006bcf78
 do_recvmmsg+0x3a0/0x810 net/socket.c:2956
 __sys_recvmmsg net/socket.c:3029 [inline]
 __do_sys_recvmmsg net/socket.c:3052 [inline]
 __se_sys_recvmmsg net/socket.c:3045 [inline]
 __x64_sys_recvmmsg+0x199/0x250 net/socket.c:3045
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f11fe7a8f19
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:00007f11ff6c1028 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: ffffffffffffffda RBX: 00007f11fea26090 RCX: 00007f11fe7a8f19
RDX: 0000000000010106 RSI: 00002000000000c0 RDI: 0000000000000003
RBP: 00007f11fe837f6d R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f11fea26128 R14: 00007f11fea26090 R15: 00007ffe20e8dec8
 </TASK>
rcu: rcu_preempt kthread starved for 10495 jiffies! g85901 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:27160 pid:17    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5393 [inline]
 __schedule+0x156f/0x4720 kernel/sched/core.c:6722
 schedule+0xbd/0x170 kernel/sched/core.c:6796
 schedule_timeout+0x188/0x2d0 kernel/time/timer.c:2168
 rcu_gp_fqs_loop+0x30d/0x15e0 kernel/rcu/tree.c:1667
 rcu_gp_kthread+0x9e/0x400 kernel/rcu/tree.c:1866
 kthread+0x2fa/0x390 kernel/kthread.c:388
 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 PID: 78 Comm: kworker/u4:5 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/06/2026
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:csd_lock_wait kernel/smp.c:311 [inline]
RIP: 0010:smp_call_function_many_cond+0xd85/0x1190 kernel/smp.c:855
Code: 45 8b 34 24 44 89 f6 83 e6 01 31 ff e8 34 06 0b 00 41 83 e6 01 49 be 00 00 00 00 00 fc ff df 75 07 e8 6f 02 0b 00 eb 38 f3 90 <42> 0f b6 04 33 84 c0 75 11 41 f7 04 24 01 00 00 00 74 1e e8 53 02
RSP: 0018:ffffc900020cf780 EFLAGS: 00000293
RAX: ffffffff817cdc4d RBX: 1ffff110171887a5 RCX: ffff8880206f1e00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc900020cf900 R08: ffffffff92223507 R09: 1ffffffff24446a0
R10: dffffc0000000000 R11: fffffbfff24446a1 R12: ffff8880b8c43d28
R13: ffff8880b8d3d380 R14: dffffc0000000000 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8880b8d00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffece9bd5ec CR3: 000000000df32000 CR4: 00000000003506e0
DR0: ffffffffffffffff DR1: 00000000000001f8 DR2: 0000000000000002
DR3: ffffffffefffff15 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1022
 on_each_cpu include/linux/smp.h:71 [inline]
 text_poke_sync arch/x86/kernel/alternative.c:2222 [inline]
 text_poke_bp_batch+0x31e/0x980 arch/x86/kernel/alternative.c:2432
 text_poke_flush arch/x86/kernel/alternative.c:2623 [inline]
 text_poke_finish+0x30/0x50 arch/x86/kernel/alternative.c:2630
 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146
 static_key_enable_cpuslocked+0x123/0x240 kernel/jump_label.c:207
 static_key_enable+0x1a/0x20 kernel/jump_label.c:220
 toggle_allocation_gate+0xa8/0x260 mm/kfence/core.c:847
 process_one_work kernel/workqueue.c:2657 [inline]
 process_scheduled_works+0xa60/0x1600 kernel/workqueue.c:2734
 worker_thread+0xa5e/0xfe0 kernel/workqueue.c:2815
 kthread+0x2fa/0x390 kernel/kthread.c:388
 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
 </TASK>