rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P4358/1:b..l
	(detected by 1, t=10502 jiffies, g=11957, q=479 ncpus=2)
task:kworker/u4:7    state:R  running task     stack:25512 pid:4358  ppid:2      flags:0x00004000
Workqueue: bat_events batadv_nc_worker
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
 preempt_schedule_irq+0xb1/0x150 kernel/sched/core.c:6873
 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+0x20f/0x490 kernel/locking/lockdep.c:5666
Code: 00 9c 8f 84 24 80 00 00 00 f6 84 24 81 00 00 00 02 0f 85 f5 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 66 43 c7 44 3d 09 00 00 43 c6 44 3d 0b
RSP: 0018:ffffc90004c1fac0 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 0000000000000000 RCX: e03b13199c464600
RDX: 0000000000000000 RSI: ffffffff8a6c1780 RDI: ffffffff8abef920
RBP: ffffc90004c1fbc8 R08: dffffc0000000000 R09: fffffbfff2119049
R10: fffffbfff2119049 R11: 1ffffffff2119048 R12: 0000000000000000
R13: 1ffff92000983f64 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+0x898/0x1160 kernel/workqueue.c:2292
 worker_thread+0xaa2/0x1250 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 10521 jiffies! g11957 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:27848 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
 schedule+0xb9/0x180 kernel/sched/core.c:6637
 schedule_timeout+0x15c/0x280 kernel/time/timer.c:2168
 rcu_gp_fqs_loop+0x2f2/0x1310 kernel/rcu/tree.c:1706
 rcu_gp_kthread+0x95/0x380 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: 4907 Comm: syz.4.101 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:should_resched arch/x86/include/asm/preempt.h:103 [inline]
RIP: 0010:__local_bh_enable_ip+0x132/0x1b0 kernel/softirq.c:428
Code: 8a e8 d2 0a c2 08 65 66 8b 05 ba 28 b5 7e 66 85 c0 75 54 bf 01 00 00 00 e8 1b 4a 09 00 e8 46 c4 38 00 fb 65 8b 05 a6 f7 b3 7e <85> c0 75 05 e8 45 09 b2 ff 48 c7 04 24 0e 36 e0 45 4b c7 04 37 00
RSP: 0018:ffffc9000c217a00 EFLAGS: 00000286
RAX: 0000000080000000 RBX: 0000000000000200 RCX: 766521b1e4185700
RDX: dffffc0000000000 RSI: ffffffff8a6c0600 RDI: ffffffff8abef920
RBP: ffffc9000c217a90 R08: dffffc0000000000 R09: ffffed1027fdcd81
R10: ffffed1027fdcd81 R11: 1ffff11027fdcd80 R12: ffffffff812f4340
R13: 0000000000000000 R14: dffffc0000000000 R15: 1ffff92001842f40
FS:  00007f3b0ebf66c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000100000001 CR3: 0000000028635000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 local_bh_enable include/linux/bottom_half.h:33 [inline]
 fpregs_unlock arch/x86/include/asm/fpu/api.h:80 [inline]
 copy_fpstate_to_sigframe+0x52d/0xcb0 arch/x86/kernel/fpu/signal.c:233
 get_sigframe arch/x86/kernel/signal.c:297 [inline]
 __setup_rt_frame arch/x86/kernel/signal.c:472 [inline]
 setup_rt_frame arch/x86/kernel/signal.c:784 [inline]
 handle_signal arch/x86/kernel/signal.c:828 [inline]
 arch_do_signal_or_restart+0x622/0x1240 arch/x86/kernel/signal.c:873
 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:87
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f3b1085f0e9
Code: 48 89 3c 25 c0 fe ff ff eb 20 0f 1f 80 00 00 00 00 45 31 c0 31 c9 ba 80 00 00 00 48 89 de bf ca 00 00 00 31 c0 e8 47 06 13 00 <8b> 03 85 c0 74 e1 c7 45 08 00 00 00 00 45 84 e4 74 2d 80 3d e3 65
RSP: 002b:00007f3b0ebf60f0 EFLAGS: 00000286
RAX: ffffffffffffffff RBX: 00007f3b10be5fa8 RCX: ffffffffffffffa8
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f3b10be5fa8
RBP: 00007f3b10be5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f3b10be6038 R14: 00007ffcbd1f67e0 R15: 00007ffcbd1f68c8
 </TASK>