rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (0 ticks this GP) idle=4acc/1/0x4000000000000000 softirq=15323/15323 fqs=0
rcu: 	(detected by 0, t=10502 jiffies, g=10585, q=96 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 6107 Comm: sed Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:variable_test_bit arch/x86/include/asm/bitops.h:-1 [inline]
RIP: 0010:arch_test_bit arch/x86/include/asm/bitops.h:233 [inline]
RIP: 0010:_test_bit include/asm-generic/bitops/instrumented-non-atomic.h:142 [inline]
RIP: 0010:hlock_class kernel/locking/lockdep.c:234 [inline]
RIP: 0010:lookup_chain_cache_add kernel/locking/lockdep.c:3820 [inline]
RIP: 0010:validate_chain+0x4e/0x2140 kernel/locking/lockdep.c:3876
Code: 8b 46 20 89 c1 81 e1 00 80 04 00 81 f9 00 00 04 00 0f 85 61 02 00 00 41 89 d4 49 89 f6 25 ff 1f 00 00 48 0f a3 05 72 2f 2e 12 <48> 89 3c 24 72 36 83 3d e5 be 31 18 00 75 2d 90 e8 cd c2 2a 03 85
RSP: 0000:ffffc900048878f8 EFLAGS: 00000047
RAX: 0000000000000000 RBX: 0000000000000001 RCX: 0000000000040000
RDX: 0000000000000000 RSI: ffff88802c5f2998 RDI: ffff88802c5f1e40
RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff84d53c5a
R10: ffffc90004887bf0 R11: fffff52000910f80 R12: 0000000000000000
R13: ffff88802c5f2970 R14: ffff88802c5f2998 R15: 2ad939879e9ec8e5
FS:  00007fc681d73c80(0000) GS:ffff888125add000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055f58bcce008 CR3: 0000000024532000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 __lock_acquire+0xab9/0xd20 kernel/locking/lockdep.c:5237
 lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868
 __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_deactivate+0x9a/0x250 lib/debugobjects.c:873
 debug_hrtimer_deactivate kernel/time/hrtimer.c:443 [inline]
 debug_deactivate+0x1d/0x200 kernel/time/hrtimer.c:483
 __run_hrtimer kernel/time/hrtimer.c:1745 [inline]
 __hrtimer_run_queues+0x2b0/0xc60 kernel/time/hrtimer.c:1841
 hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1903
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1041 [inline]
 __sysvec_apic_timer_interrupt+0x10b/0x410 arch/x86/kernel/apic/apic.c:1058
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1052 [inline]
 sysvec_apic_timer_interrupt+0x52/0xc0 arch/x86/kernel/apic/apic.c:1052
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0033:0x7fc681ed5900
Code: 00 00 48 8b 05 a1 74 13 00 64 80 38 00 75 1b e8 76 f6 ff ff 48 3b 2d f7 78 13 00 73 0d 64 49 8b 14 24 48 85 d2 75 96 0f 1f 00 <80> 3d 19 f8 13 00 00 0f 85 13 01 00 00 48 8b 05 64 74 13 00 64 48
RSP: 002b:00007ffe01058090 EFLAGS: 00000246
RAX: 0000000000000080 RBX: 0000000000000078 RCX: 0000000000000000
RDX: 000055f58bcce010 RSI: 00007ffe01058130 RDI: 0000000000000078
RBP: 0000000000000006 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: ffffffffffffffc0
R13: 00007ffe01058130 R14: 00007fc681e0f4d0 R15: 00000000fbada488
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g10585 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=1 timer-softirq=3159
rcu: rcu_preempt kthread starved for 10502 jiffies! g10585 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:27224 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5360 [inline]
 __schedule+0x1798/0x4cc0 kernel/sched/core.c:6964
 __schedule_loop kernel/sched/core.c:7046 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:7061
 schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2083
 rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2285
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
sched: DL replenish lagged too much