rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P4918/1:b..l
	(detected by 0, t=10502 jiffies, g=97161, q=319 ncpus=2)
task:kworker/u4:17   state:R  running task     stack:20728 pid:4918  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:debug_lockdep_rcu_enabled+0x25/0x30 kernel/rcu/update.c:281
Code: 00 00 cc cc 00 31 c0 83 3d b7 69 f3 03 00 74 1d 83 3d 42 9d f3 03 00 74 14 65 48 8b 0d 94 14 d6 75 31 c0 83 b9 dc 0a 00 00 00 <0f> 94 c0 c3 00 00 cc cc 00 00 cc 48 8b 3c 24 e8 47 fb ff ff 66 90
RSP: 0018:ffffc9000bd27bd8 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffff88807cc50000
RDX: 0000000000000000 RSI: ffffffff8adf0c00 RDI: ffffffff8adf0bc0
RBP: fffffffffffffe38 R08: dffffc0000000000 R09: 1ffffffff215e648
R10: dffffc0000000000 R11: fffffbfff215e649 R12: dffffc0000000000
R13: ffffffff89f595be R14: ffff888058438c80 R15: 00000000000003b6
 rcu_read_unlock include/linux/rcupdate.h:820 [inline]
 batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:412 [inline]
 batadv_nc_worker+0x1f0/0x600 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 10519 jiffies! g97161 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->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:R  running task     stack:26768 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: 0 PID: 0 Comm: swapper/0 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:default_idle+0xb/0x10 arch/x86/kernel/process.c:742
Code: 48 89 df e8 a7 10 9d f7 e9 44 ff ff ff e8 7d 07 f6 ff 00 00 cc cc 00 00 cc cc 00 00 cc cc 00 66 90 0f 00 2d 87 5d 50 00 fb f4 <c3> 0f 1f 40 00 41 57 41 56 53 49 be 00 00 00 00 00 fc ff df 65 48
RSP: 0018:ffffffff8c807d88 EFLAGS: 000002c6
RAX: 0c3ecad056424800 RBX: ffffffff8a3651a7 RCX: 0c3ecad056424800
RDX: 0000000000000001 RSI: ffffffff8a8c1220 RDI: ffffffff8adf0c20
RBP: ffffffff8c807ec0 R08: ffff8880b8e3580b R09: 1ffff110171c6b01
R10: dffffc0000000000 R11: ffffed10171c6b02 R12: 1ffffffff1900fbc
R13: dffffc0000000000 R14: ffffffff8c8bc740 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ff29a58a000 CR3: 000000005fa62000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 default_idle_call+0x84/0xc0 kernel/sched/idle.c:109
 cpuidle_idle_call kernel/sched/idle.c:191 [inline]
 do_idle+0x20d/0x5a0 kernel/sched/idle.c:303
 cpu_startup_entry+0x3f/0x60 kernel/sched/idle.c:401
 rest_init+0x2dc/0x300 init/main.c:745
 arch_call_rest_init+0xa/0xa init/main.c:905
 start_kernel+0x493/0x53c init/main.c:1152
 secondary_startup_64_no_verify+0xcf/0xdb
 </TASK>