rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	(detected by 1, t=10502 jiffies, g=46189, q=211 ncpus=2)
rcu: All QSes seen, last rcu_preempt kthread activity 10502 (4295001541-4294991039), jiffies_till_next_fqs=1, root ->qsmask 0x0
rcu: rcu_preempt kthread starved for 10502 jiffies! g46189 f0x2 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:27304 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5382 [inline]
 __schedule+0x116f/0x5de0 kernel/sched/core.c:6767
 __schedule_loop kernel/sched/core.c:6845 [inline]
 schedule+0xe7/0x3a0 kernel/sched/core.c:6860
 schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x1ea/0xb00 kernel/rcu/tree.c:2046
 rcu_gp_kthread+0x270/0x380 kernel/rcu/tree.c:2248
 kthread+0x3c2/0x780 kernel/kthread.c:464
 ret_from_fork+0x45/0x80 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:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 3 Comm: pool_workqueue_ Not tainted 6.15.0-rc2-syzkaller-00042-g1a1d569a75f3 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
RIP: 0010:hlock_class kernel/locking/lockdep.c:245 [inline]
RIP: 0010:mark_lock+0x63/0x610 kernel/locking/lockdep.c:4732
Code: 6d 41 bd 01 00 00 00 89 d9 41 d3 e5 4d 63 ed 41 0f b7 44 24 20 66 25 ff 1f 0f b7 c0 48 0f a3 05 43 ba 15 14 0f 83 86 00 00 00 <48> 8d 04 80 48 8d 04 80 48 8d 04 c5 60 af ad 95 4c 89 ea 48 23 50
RSP: 0018:ffffc90000007b90 EFLAGS: 00000007
RAX: 0000000000000e36 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffff88801c6fd370 RDI: ffff88801c6fc880
RBP: ffffc90000007c28 R08: 0000000000080000 R09: 0000000000000001
R10: 0000000000000000 R11: ffff88802cf27300 R12: ffff88801c6fd370
R13: 0000000000000001 R14: ffff88801c6fc880 R15: ffff88801c6fc880
FS:  0000000000000000(0000) GS:ffff8881249b0000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c39a1b1 CR3: 000000007d5d6000 CR4: 00000000003526f0
Call Trace:
 <IRQ>
 mark_usage kernel/locking/lockdep.c:4640 [inline]
 __lock_acquire+0x95e/0x1ba0 kernel/locking/lockdep.c:5189
 lock_acquire kernel/locking/lockdep.c:5866 [inline]
 lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5823
 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
 _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154
 spin_lock include/linux/spinlock.h:351 [inline]
 advance_sched+0xd9/0xc80 net/sched/sch_taprio.c:924
 __run_hrtimer kernel/time/hrtimer.c:1761 [inline]
 __hrtimer_run_queues+0x1ff/0xad0 kernel/time/hrtimer.c:1825
 hrtimer_interrupt+0x397/0x8e0 kernel/time/hrtimer.c:1887
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline]
 __sysvec_apic_timer_interrupt+0x108/0x3f0 arch/x86/kernel/apic/apic.c:1055
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline]
 sysvec_apic_timer_interrupt+0x9f/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:preempt_schedule_irq+0x4c/0x90 kernel/sched/core.c:7090
Code: df 55 65 48 8b 2d cc 72 33 08 53 48 89 eb 48 c1 eb 03 48 01 c3 bf 01 00 00 00 e8 0f a1 15 f6 e8 5a 74 4f f6 fb bf 01 00 00 00 <e8> af 99 ff ff 9c 58 fa f6 c4 02 75 1e bf 01 00 00 00 e8 5d 4b 15
RSP: 0018:ffffc90000087cd8 EFLAGS: 00000202
RAX: 000000000000242f RBX: ffffed10038df910 RCX: ffffffff81c300bf
RDX: 0000000000000000 RSI: ffffffff8dbef557 RDI: 0000000000000001
RBP: ffff88801c6fc880 R08: 0000000000000001 R09: 0000000000000001
R10: ffffffff90866017 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 irqentry_exit+0x36/0x90 kernel/entry/common.c:354
 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:707
RIP: 0010:lockdep_unregister_key+0xdd/0x130 kernel/locking/lockdep.c:6613
Code: 48 89 ef e8 b5 fe ff ff 48 89 ef e8 cd e5 ff ff 89 c3 e8 f6 ee ff ff 9c 58 f6 c4 02 75 52 41 f7 c4 00 02 00 00 74 01 fb 84 db <75> 1b 5b 5d 41 5c e9 58 5d 0a 00 8b 05 d6 d1 ee 0e 31 db 85 c0 74
RSP: 0018:ffffc90000087da0 EFLAGS: 00000246
RAX: 0000000000000046 RBX: 0000000000000000 RCX: 0000000000000001
RDX: 0000000000000000 RSI: ffffffff8dce06ea RDI: ffffffff8bf46500
RBP: ffffffff972bb018 R08: 000000000000b604 R09: ffffffff95c81bc8
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000246
R13: ffff88802994d400 R14: ffff88802994d408 R15: ffff888066940001
 wq_unregister_lockdep kernel/workqueue.c:4816 [inline]
 pwq_release_workfn+0x5e6/0xa70 kernel/workqueue.c:5112
 kthread_worker_fn+0x30d/0xc50 kernel/kthread.c:1010
 kthread+0x3c2/0x780 kernel/kthread.c:464
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>