rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	(detected by 0, t=10502 jiffies, g=85889, q=1345 ncpus=2)
rcu: All QSes seen, last rcu_preempt kthread activity 10452 (4295009573-4294999121), jiffies_till_next_fqs=1, root ->qsmask 0x0
rcu: rcu_preempt kthread starved for 10452 jiffies! g85889 f0x2 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:26792 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5357 [inline]
 __schedule+0x1798/0x4cc0 kernel/sched/core.c:6961
 __schedule_loop kernel/sched/core.c:7043 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:7058
 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+0x70e/0x8a0 kernel/kthread.c:463
 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 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 13 Comm: kworker/u8:1 Not tainted 6.16.0-next-20250731-syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Workqueue: bat_events batadv_nc_worker
RIP: 0010:separate_irq_context kernel/locking/lockdep.c:4689 [inline]
RIP: 0010:__lock_acquire+0x705/0xd20 kernel/locking/lockdep.c:5221
Code: 00 48 83 7c 24 28 00 75 1e 83 3d a5 bc 0b 18 00 0f 95 c0 49 83 ff ff 0f 94 c1 08 c1 bd 01 00 00 00 0f 84 1d 05 00 00 4d 89 3e <8b> 9f e8 0a 00 00 48 85 db 0f 84 81 00 00 00 83 fb 31 0f 83 e0 05
RSP: 0018:ffffc90000a08ad0 EFLAGS: 00000002
RAX: 0000000000000000 RBX: 0000000000000004 RCX: ffffffff93469330
RDX: 0000000000000008 RSI: ffff88801cea8b90 RDI: ffff88801cea8000
RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff84d0790a
R10: ffffc90000a08cb0 R11: fffff52000141198 R12: 0000000000000002
R13: 0000000000000002 R14: ffff88801cea8b90 R15: 4d4df099ab2b819a
FS:  0000000000000000(0000) GS:ffff888125d43000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fdf32926000 CR3: 000000005eac0000 CR4: 00000000003526f0
Call Trace:
 <IRQ>
 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:450 [inline]
 debug_deactivate+0x1d/0x200 kernel/time/hrtimer.c:490
 __run_hrtimer kernel/time/hrtimer.c:1729 [inline]
 __hrtimer_run_queues+0x2b0/0xc60 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:lockdep_enabled kernel/locking/lockdep.c:118 [inline]
RIP: 0010:lock_release+0x63/0x3e0 kernel/locking/lockdep.c:5881
Code: 00 89 c0 48 0f a3 05 0c ab 04 0e 73 16 e8 45 f1 08 00 84 c0 75 0d f6 05 df 96 ee 0d 01 0f 84 ad 02 00 00 83 3d 2d dc 04 0e 00 <0f> 84 44 02 00 00 65 8b 05 e0 a2 00 11 85 c0 0f 85 35 02 00 00 65
RSP: 0018:ffffc900001279b8 EFLAGS: 00000202
RAX: 0000000000000001 RBX: ffff888025374400 RCX: 361ebd12d31cca00
RDX: 0000000000000000 RSI: ffffffff8be340e0 RDI: ffffffff8be340a0
RBP: fffffffffffffe38 R08: 0000000000000000 R09: ffffffff8b44b1a2
R10: dffffc0000000000 R11: ffffffff8b44b0d0 R12: dffffc0000000000
R13: ffffffff8b44b1a2 R14: ffffffff8e139f20 R15: 0000000000000201
 rcu_lock_release include/linux/rcupdate.h:341 [inline]
 rcu_read_unlock include/linux/rcupdate.h:871 [inline]
 batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:412 [inline]
 batadv_nc_worker+0x28c/0x610 net/batman-adv/network-coding.c:719
 process_one_work kernel/workqueue.c:3236 [inline]
 process_scheduled_works+0xade/0x17b0 kernel/workqueue.c:3319
 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400
 kthread+0x70e/0x8a0 kernel/kthread.c:463
 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>