rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	(detected by 1, t=10544 jiffies, g=10913, q=1059 ncpus=2)
rcu: All QSes seen, last rcu_preempt kthread activity 4279 (4294960205-4294955926), jiffies_till_next_fqs=1, root ->qsmask 0x0
rcu: rcu_preempt kthread starved for 4279 jiffies! g10913 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:27320 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5397 [inline]
 __schedule+0x16f5/0x4d00 kernel/sched/core.c:6786
 __schedule_loop kernel/sched/core.c:6864 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:6879
 schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2054
 rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2256
 kthread+0x70e/0x8a0 kernel/kthread.c:464
 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
 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: 9 Comm: kworker/0:0 Not tainted 6.16.0-rc6-syzkaller-00135-gcf074eca0065 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: events_power_efficient gc_worker
RIP: 0010:validate_chain+0x24/0x2140 kernel/locking/lockdep.c:3878
Code: 90 90 90 90 90 90 55 41 57 41 56 41 55 41 54 53 48 81 ec e0 00 00 00 49 89 cf 65 48 8b 05 24 4e 01 11 48 89 84 24 d8 00 00 00 <8b> 46 20 89 c1 81 e1 00 80 04 00 81 f9 00 00 04 00 0f 85 61 02 00
RSP: 0018:ffffc90000007998 EFLAGS: 00000082
RAX: 6b6cd01abcebc800 RBX: 0000000000000003 RCX: 07b24d8723fa41a2
RDX: 0000000000000000 RSI: ffff88801d288b68 RDI: ffff88801d288000
RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff84c681eb
R10: ffffc90000007ca0 R11: fffff52000000f96 R12: 0000000043efe266
R13: ffff88801d288af0 R14: ffff88801d288b68 R15: 07b24d8723fa41a2
FS:  0000000000000000(0000) GS:ffff888125c23000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffc536beff8 CR3: 0000000033d3e000 CR4: 00000000003526f0
Call Trace:
 <IRQ>
 __lock_acquire+0xab9/0xd20 kernel/locking/lockdep.c:5240
 lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
 _raw_spin_lock_irqsave+0xa7/0xf0 kernel/locking/spinlock.c:162
 debug_object_activate+0xbb/0x420 lib/debugobjects.c:818
 debug_hrtimer_activate kernel/time/hrtimer.c:445 [inline]
 debug_activate kernel/time/hrtimer.c:484 [inline]
 enqueue_hrtimer+0x30/0x3a0 kernel/time/hrtimer.c:1088
 __run_hrtimer kernel/time/hrtimer.c:1778 [inline]
 __hrtimer_run_queues+0x656/0xc60 kernel/time/hrtimer.c:1825
 hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1887
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1039 [inline]
 __sysvec_apic_timer_interrupt+0x108/0x410 arch/x86/kernel/apic/apic.c:1056
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
 sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1050
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:__sanitizer_cov_trace_cmp4+0x83/0x90 kernel/kcov.c:289
Code: 8d 52 28 4d 39 ca 77 22 89 ff 89 f6 49 ff c0 4c 89 01 48 c7 44 11 08 04 00 00 00 48 89 7c 11 10 48 89 74 11 18 48 89 44 11 20 <c3> cc cc cc cc cc 0f 1f 80 00 00 00 00 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc900000e7918 EFLAGS: 00000293
RAX: ffffffff899ede33 RBX: dffffc0000000000 RCX: 0000000000000000
RDX: ffff88801d288000 RSI: 0000000000040000 RDI: 000000000001e21f
RBP: ffffc900000e7a70 R08: ffffffff8fa1d6f7 R09: 1ffffffff1f43ade
R10: dffffc0000000000 R11: fffffbfff1f43adf R12: ffff8880b8639700
R13: ffff88801ce81918 R14: 000000000001e21f R15: 0000000000040000
 gc_worker+0xc23/0x1380 net/netfilter/nf_conntrack_core.c:-1
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3321
 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402
 kthread+0x70e/0x8a0 kernel/kthread.c:464
 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.144 msecs