rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P11/1:b..l
	(detected by 1, t=10503 jiffies, g=11313, q=196 ncpus=2)
task:kworker/u4:1    state:R  running task     stack:25304 pid:11    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:native_save_fl arch/x86/include/asm/irqflags.h:35 [inline]
RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:70 [inline]
RIP: 0010:arch_local_irq_save arch/x86/include/asm/irqflags.h:106 [inline]
RIP: 0010:lock_acquire+0x166/0x4a0 kernel/locking/lockdep.c:5658
Code: 0f 85 2f 02 00 00 41 83 3e 00 0f 85 18 01 00 00 43 c6 44 3d 08 00 48 c7 84 24 a0 00 00 00 00 00 00 00 9c 8f 84 24 a0 00 00 00 <4c> 8b b4 24 a0 00 00 00 43 c6 44 3d 08 f8 fa 48 c7 c7 00 1f 8c 8a
RSP: 0018:ffffc90000107ac0 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: c911fe707545ea00
RDX: 0000000000000000 RSI: ffffffff8adf0c00 RDI: ffffffff8adf0bc0
RBP: ffffc90000107bc8 R08: ffffffff8e1fc32f R09: 1ffffffff1c3f865
R10: dffffc0000000000 R11: fffffbfff1c3f866 R12: 0000000000000001
R13: 1ffff92000020f64 R14: ffff88813fea465c 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 starved for 10528 jiffies! g11313 f0x0 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:27736 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:
CPU: 1 PID: 4532 Comm: syz.1.30 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
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 ae 54 2e f7 48 89 df e8 f6 1c 2f f7 e8 71 6d 52 f7 fb bf 01 00 00 00 <e8> 96 7d 22 f7 65 8b 05 57 01 cc 75 85 c0 74 02 5b c3 e8 a4 15 ca
RSP: 0018:ffffc90003847cf0 EFLAGS: 00000286
RAX: 563020a3b1547400 RBX: ffff8880568665c0 RCX: 563020a3b1547400
RDX: dffffc0000000000 RSI: ffffffff8a8c1220 RDI: 0000000000000001
RBP: ffffc90003847f10 R08: ffff8880568665c3 R09: 1ffff1100ad0ccb8
R10: dffffc0000000000 R11: ffffed100ad0ccb9 R12: 1ffff92000708fa8
R13: dffffc0000000000 R14: 00007f7dfd7c4b38 R15: ffff888027078000
FS:  00007f7dfd7c56c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000c006ada000 CR3: 000000007e449000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 __ia32_sys_rt_sigreturn+0x1ad/0x760 arch/x86/kernel/signal.c:673
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f7dfc93c0d9
Code: 11 06 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 90 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 c7 c0 0f 00 00 00 0f 05 <0f> 1f 80 00 00 00 00 48 81 ec 48 01 00 00 49 89 d0 64 48 8b 0c 25
RSP: 002b:00007f7dfd7c4b40 EFLAGS: 00000206 ORIG_RAX: 000000000000000f
RAX: ffffffffffffffda RBX: 00007f7dfcc15fa8 RCX: 00007f7dfc93c0d9
RDX: 00007f7dfd7c4b40 RSI: 00007f7dfd7c4c70 RDI: 0000000000000021
RBP: 00007f7dfcc15fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 00007f7dfcc16038 R14: 00007ffec1060420 R15: 00007ffec1060508
 </TASK>