rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P2919/1:b..l
	(detected by 1, t=10502 jiffies, g=9861, q=27 ncpus=2)
task:kworker/u4:5    state:R  running task     stack:25776 pid:2919  ppid:2      flags:0x00004000
Workqueue: bat_events batadv_nc_worker
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5245 [inline]
 __schedule+0x11d1/0x40e0 kernel/sched/core.c:6562
 preempt_schedule_irq+0xbb/0x160 kernel/sched/core.c:6874
 irqentry_exit+0x63/0x70 kernel/entry/common.c:439
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:lock_acquire+0x225/0x4a0 kernel/locking/lockdep.c:5666
Code: f7 84 24 80 00 00 00 00 02 00 00 43 c6 44 3d 04 f8 0f 85 f0 00 00 00 41 f7 c6 00 02 00 00 74 01 fb 48 c7 44 24 60 0e 36 e0 45 <4b> c7 44 3d 00 00 00 00 00 43 c7 44 3d 08 00 00 00 00 65 48 8b 04
RSP: 0018:ffffc9000c927ac0 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 3c3fbab9eb5acf00
RDX: 0000000000000000 RSI: ffffffff8a8c22a0 RDI: ffffffff8adf13a0
RBP: ffffc9000c927bc8 R08: dffffc0000000000 R09: 1ffffffff215f248
R10: dffffc0000000000 R11: fffffbfff215f249 R12: 0000000000000000
R13: 1ffff92001924f64 R14: 0000000000000246 R15: dffffc0000000000
 rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
 rcu_read_lock include/linux/rcupdate.h:791 [inline]
 batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline]
 batadv_nc_worker+0xeb/0x600 net/batman-adv/network-coding.c:719
 process_one_work+0x8a2/0x1160 kernel/workqueue.c:2292
 worker_thread+0xaa2/0x1270 kernel/workqueue.c:2439
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10527 jiffies! g9861 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=3508
rcu: rcu_preempt kthread starved for 10528 jiffies! g9861 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:26864 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5245 [inline]
 __schedule+0x11d1/0x40e0 kernel/sched/core.c:6562
 schedule+0xb9/0x180 kernel/sched/core.c:6638
 schedule_timeout+0x184/0x2d0 kernel/time/timer.c:2168
 rcu_gp_fqs_loop+0x303/0x1340 kernel/rcu/tree.c:1706
 rcu_gp_kthread+0x99/0x3b0 kernel/rcu/tree.c:1905
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </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 PID: 4459 Comm: syz.0.28 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
RIP: 0010:arch_irqs_disabled_flags arch/x86/include/asm/irqflags.h:125 [inline]
RIP: 0010:arch_irqs_disabled arch/x86/include/asm/irqflags.h:132 [inline]
RIP: 0010:seqcount_lockdep_reader_access+0x144/0x1d0 include/linux/seqlock.h:104
Code: 48 89 de e8 8e 0e f2 ff e8 a9 2d 16 00 48 b8 04 00 00 00 00 fc ff df 41 c6 04 06 00 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 <48> 8b 5c 24 20 41 c6 04 06 f8 48 89 de 48 81 e6 00 02 00 00 31 ff
RSP: 0018:ffffc90000007d60 EFLAGS: 00000046
RAX: dffffc0000000004 RBX: ffffffff8172b1db RCX: 85d97ba03a671a00
RDX: 0000000000000000 RSI: ffffffff8a8c22a0 RDI: ffffffff8adf13a0
RBP: ffffc90000007e10 R08: ffffffff8e1ff42f R09: 1ffffffff1c3fe85
R10: dffffc0000000000 R11: fffffbfff1c3fe86 R12: 0000000000000000
R13: 0000002d1f615200 R14: 1ffff92000000fac R15: dffffc0000000000
FS:  00007f73965896c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2fc1eff8 CR3: 0000000055d20000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 timekeeping_get_delta kernel/time/timekeeping.c:254 [inline]
 timekeeping_get_ns kernel/time/timekeeping.c:388 [inline]
 ktime_get+0x7b/0x270 kernel/time/timekeeping.c:848
 clockevents_program_event+0xe2/0x310 kernel/time/clockevents.c:326
 hrtimer_interrupt+0x59d/0x9c0 kernel/time/hrtimer.c:1886
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1107 [inline]
 __sysvec_apic_timer_interrupt+0x153/0x5a0 arch/x86/kernel/apic/apic.c:1124
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
 sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1118
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x25/0x40 kernel/locking/spinlock.c:202
Code: 00 00 00 66 90 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 0e b0 2c f7 48 89 df e8 56 78 2d f7 e8 21 cf 50 f7 fb bf 01 00 00 00 <e8> a6 dc 20 f7 65 8b 05 f7 5f ca 75 85 c0 74 02 5b c3 e8 44 74 c8
RSP: 0018:ffffc90004bd7b98 EFLAGS: 00000282
RAX: 85d97ba03a671a00 RBX: ffff888057d2dc80 RCX: 85d97ba03a671a00
RDX: dffffc0000000000 RSI: ffffffff8a8c1120 RDI: 0000000000000001
RBP: ffff888057d2e118 R08: ffff888057d2dc83 R09: 1ffff1100afa5b90
R10: dffffc0000000000 R11: ffffed100afa5b91 R12: 1ffff1100afa5c23
R13: 0000000000000021 R14: dffffc0000000000 R15: 0000000000000000
 spin_unlock_irq include/linux/spinlock.h:401 [inline]
 get_signal+0x1163/0x1350 kernel/signal.c:2874
 arch_do_signal_or_restart+0xc4/0x1350 arch/x86/kernel/signal.c:871
 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
 syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f739579c817
Code: 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 <0f> 05 48 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89
RSP: 002b:00007f73965890e8 EFLAGS: 00000246
RAX: 00000000000000ca RBX: 00007f7395a16098 RCX: 00007f739579c819
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f7395a16098
RBP: 00007f7395a16090 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f7395a16128 R14: 00007fff26e390d0 R15: 00007fff26e391b8
 </TASK>