rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	(detected by 1, t=10506 jiffies, g=15269, q=488 ncpus=2)
rcu: All QSes seen, last rcu_preempt kthread activity 10506 (4294967702-4294957196), jiffies_till_next_fqs=1, root ->qsmask 0x0
rcu: rcu_preempt kthread timer wakeup didn't happen for 10505 jiffies! g15269 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x200
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=4272
rcu: rcu_preempt kthread starved for 10506 jiffies! g15269 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x200 ->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 stack:27832 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5382 [inline]
 __schedule+0x10e9/0x6820 kernel/sched/core.c:7183
 __schedule_loop kernel/sched/core.c:7262 [inline]
 schedule+0xdd/0x390 kernel/sched/core.c:7277
 schedule_timeout+0x127/0x280 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x1a9/0x900 kernel/rcu/tree.c:2095
 rcu_gp_kthread+0x179/0x230 kernel/rcu/tree.c:2297
 kthread+0x370/0x450 kernel/kthread.c:436
 ret_from_fork+0x72b/0xd50 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:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
RIP: 0010:hlock_class kernel/locking/lockdep.c:234 [inline]
RIP: 0010:mark_lock+0x52/0xa20 kernel/locking/lockdep.c:4731
Code: 89 d3 83 fa 08 74 6d 41 be 01 00 00 00 89 d9 41 d3 e6 4d 63 f6 41 0f b7 44 24 20 66 25 ff 1f 0f b7 c0 48 0f a3 05 be 3d 33 14 <73> 5b 48 8d 04 80 48 8d 04 80 48 8d 04 c5 60 0c 18 96 4c 89 f1 48
RSP: 0018:ffffc90000007b50 EFLAGS: 00000047
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff8e496178 RDI: ffffffff8e4955c0
RBP: ffffc90000007bf0 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000001 R12: ffffffff8e496178
R13: ffffffff8e4955c0 R14: 0000000000000001 R15: 0000000000000002
FS:  0000000000000000(0000) GS:ffff88812430d000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f6a1ce49ff8 CR3: 000000002733d000 CR4: 00000000003526f0
Call Trace:
 <IRQ>
 mark_usage kernel/locking/lockdep.c:4639 [inline]
 __lock_acquire+0x10ff/0x2630 kernel/locking/lockdep.c:5191
 lock_acquire kernel/locking/lockdep.c:5868 [inline]
 lock_acquire+0x1b1/0x370 kernel/locking/lockdep.c:5825
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:132 [inline]
 _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:166
 debug_object_activate+0x144/0x490 lib/debugobjects.c:835
 debug_hrtimer_activate kernel/time/hrtimer.c:485 [inline]
 debug_activate kernel/time/hrtimer.c:528 [inline]
 enqueue_hrtimer+0x75/0x2f0 kernel/time/hrtimer.c:1109
 __run_hrtimer kernel/time/hrtimer.c:1946 [inline]
 __hrtimer_run_queues+0x73d/0xa00 kernel/time/hrtimer.c:1994
 hrtimer_interrupt+0x3e5/0x940 kernel/time/hrtimer.c:2113
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
 __sysvec_apic_timer_interrupt+0x10b/0x460 arch/x86/kernel/apic/apic.c:1067
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline]
 sysvec_apic_timer_interrupt+0x9e/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:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:63
Code: c6 88 02 e9 43 43 03 00 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 83 6c 15 00 fb f4 <c3> cc cc cc cc 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90
RSP: 0018:ffffffff8e407e00 EFLAGS: 00000242
RAX: 00000000000c1731 RBX: ffffffff8e4955c0 RCX: ffffffff8b962005
RDX: 0000000000000000 RSI: ffffffff8df37a35 RDI: ffffffff8c1b4ee0
RBP: 0000000000000000 R08: 0000000000000001 R09: ffffed10170867ad
R10: ffff8880b8433d6b R11: 0000000000000000 R12: 0000000000000000
R13: fffffbfff1c92ab8 R14: 0000000000000000 R15: ffffffff90da9b10
 arch_safe_halt arch/x86/include/asm/paravirt.h:62 [inline]
 default_idle+0x9/0x10 arch/x86/kernel/process.c:767
 default_idle_call+0x6c/0xb0 kernel/sched/idle.c:122
 cpuidle_idle_call kernel/sched/idle.c:199 [inline]
 do_idle+0x464/0x590 kernel/sched/idle.c:352
 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:451
 rest_init+0x251/0x260 init/main.c:762
 start_kernel+0x484/0x490 init/main.c:1220
 x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310
 x86_64_start_kernel+0x12b/0x130 arch/x86/kernel/head64.c:291
 common_startup_64+0x13e/0x148
 </TASK>