rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P135/1:b..l
rcu: 	(detected by 1, t=10502 jiffies, g=20573, q=563 ncpus=2)
task:kworker/u8:5    state:R  running task     stack:20312 pid:135   tgid:135   ppid:2      task_flags:0x4208060 flags:0x00080000
Workqueue: bat_events batadv_iv_send_outstanding_bat_ogm_packet
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5295 [inline]
 __schedule+0x153e/0x4fe0 kernel/sched/core.c:6907
 preempt_schedule_notrace+0x57/0x90 kernel/sched/core.c:7184
 preempt_schedule_notrace_thunk+0x16/0x30 arch/x86/entry/thunk.S:13
 rcu_is_watching+0x7f/0xb0 kernel/rcu/tree.c:753
 rcu_read_lock include/linux/rcupdate.h:851 [inline]
 batadv_iv_ogm_slide_own_bcast_window net/batman-adv/bat_iv_ogm.c:761 [inline]
 batadv_iv_ogm_schedule_buff net/batman-adv/bat_iv_ogm.c:833 [inline]
 batadv_iv_ogm_schedule+0x47b/0xf50 net/batman-adv/bat_iv_ogm.c:873
 batadv_iv_send_outstanding_bat_ogm_packet+0x6c8/0x7e0 net/batman-adv/bat_iv_ogm.c:1709
 process_one_work+0x949/0x15a0 kernel/workqueue.c:3279
 process_scheduled_works kernel/workqueue.c:3362 [inline]
 worker_thread+0x9af/0xee0 kernel/workqueue.c:3443
 kthread+0x388/0x470 kernel/kthread.c:467
 ret_from_fork+0x51b/0xa40 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
rcu: rcu_preempt kthread starved for 10520 jiffies! g20573 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:27688 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5295 [inline]
 __schedule+0x153e/0x4fe0 kernel/sched/core.c:6907
 preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:7091
 preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:179 [inline]
 _raw_spin_unlock_irqrestore+0x74/0x80 kernel/locking/spinlock.c:194
 timer_init_key_on_stack+0x3c/0x110 kernel/time/timer.c:816
 schedule_timeout+0x146/0x2c0 kernel/time/sleep_timeout.c:96
 rcu_gp_fqs_loop+0x312/0x11d0 kernel/rcu/tree.c:2095
 rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2297
 kthread+0x388/0x470 kernel/kthread.c:467
 ret_from_fork+0x51b/0xa40 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: 6558 Comm: syz.1.24 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/13/2026
RIP: 0010:lookup_chain_cache kernel/locking/lockdep.c:3801 [inline]
RIP: 0010:lookup_chain_cache_add kernel/locking/lockdep.c:3821 [inline]
RIP: 0010:validate_chain kernel/locking/lockdep.c:3876 [inline]
RIP: 0010:__lock_acquire+0xb17/0x2cf0 kernel/locking/lockdep.c:5237
Code: 04 75 0e 48 c7 c6 68 82 f0 8d 67 48 0f b9 3a 90 48 bb eb 83 b5 80 46 86 c8 61 48 0f af dd 48 c1 eb 2d 48 8b 04 dd c0 b3 db 93 <48> 85 c0 0f 94 c1 48 83 c0 f8 0f 94 c2 08 ca 0f 84 1c 01 00 00 e8
RSP: 0018:ffffc9000416fb38 EFLAGS: 00000006
RAX: ffffffff941ff038 RBX: 000000000002c3b8 RCX: 0000000000040000
RDX: 0000000072714046 RSI: 00000000f7ea3084 RDI: ffff8880272b1e40
RBP: 89b8f3a49543179a R08: ffffffff818997b2 R09: ffff888031af8018
R10: dffffc0000000000 R11: fffffbfff2023a57 R12: ffff8880272b2960
R13: ffff8880272b2960 R14: ffff8880272b1e40 R15: 0000000000000000
FS:  00007f92b73db6c0(0000) GS:ffff8881252a1000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fe0d67e8640 CR3: 0000000071e56000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 lock_acquire+0x106/0x330 kernel/locking/lockdep.c:5868
 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:142 [inline]
 _raw_spin_lock_irq+0x3d/0x50 kernel/locking/spinlock.c:170
 spin_lock_irq include/linux/spinlock.h:374 [inline]
 __set_current_blocked kernel/signal.c:3220 [inline]
 set_current_blocked kernel/signal.c:3206 [inline]
 signal_delivered kernel/signal.c:3070 [inline]
 signal_setup_done+0x202/0x3b0 kernel/signal.c:3082
 handle_signal arch/x86/kernel/signal.c:312 [inline]
 arch_do_signal_or_restart+0x4be/0x830 arch/x86/kernel/signal.c:339
 __exit_to_user_mode_loop kernel/entry/common.c:41 [inline]
 exit_to_user_mode_loop+0x86/0x480 kernel/entry/common.c:75
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline]
 do_syscall_64+0x2b7/0xf80 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f92b644f700
Code: 44 24 20 0f 29 44 24 30 0f 29 44 24 40 48 8b 44 24 08 ff d0 48 83 c4 50 31 c0 5b 5d 41 5c 41 5d 41 5e c3 0f 1f 80 00 00 00 00 <c3> 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 c3 66 66 2e 0f 1f
RSP: 002b:00007f92b73daab8 EFLAGS: 00000206
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 00007f92b73daac0 RSI: 00007f92b73dabf0 RDI: 0000000000000011
RBP: 00007f92b6648767 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f92b6806038 R14: 00007f92b6805fa0 R15: 00007fff46adc598
 </TASK>