rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P13352/1:b..l rcu: (detected by 0, t=10502 jiffies, g=80661, q=331 ncpus=2) task:kworker/u8:12 state:R running task stack:24216 pid:13352 tgid:13352 ppid:2 task_flags:0x4208060 flags:0x00004000 Workqueue: bat_events batadv_iv_send_outstanding_bat_ogm_packet Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x1190/0x5de0 kernel/sched/core.c:6961 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7288 irqentry_exit+0x36/0x90 kernel/entry/common.c:197 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lock_release+0x183/0x2f0 kernel/locking/lockdep.c:5893 Code: 0f c1 05 f8 4d 3f 12 83 f8 01 0f 85 1d 01 00 00 9c 58 f6 c4 02 0f 85 08 01 00 00 41 f7 c5 00 02 00 00 74 01 fb 48 8b 44 24 10 <65> 48 2b 05 0d 0c 3f 12 0f 85 58 01 00 00 48 83 c4 18 5b 41 5c 41 RSP: 0018:ffffc90000ad7a78 EFLAGS: 00000206 RAX: 13b87c3472fe4e00 RBX: ffffffff8e5c15a0 RCX: ffffc90000ad7a84 RDX: 0000000000000003 RSI: ffffffff8de2d740 RDI: ffffffff8c163400 RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: ffffffff8b5c8280 R13: 0000000000000202 R14: ffff88803070a440 R15: 0000000000000004 rcu_lock_release include/linux/rcupdate.h:341 [inline] rcu_read_unlock include/linux/rcupdate.h:871 [inline] batadv_iv_ogm_slide_own_bcast_window net/batman-adv/bat_iv_ogm.c:779 [inline] batadv_iv_ogm_schedule_buff+0x785/0x14c0 net/batman-adv/bat_iv_ogm.c:834 batadv_iv_ogm_schedule net/batman-adv/bat_iv_ogm.c:874 [inline] batadv_iv_ogm_schedule net/batman-adv/bat_iv_ogm.c:867 [inline] batadv_iv_send_outstanding_bat_ogm_packet+0x329/0x920 net/batman-adv/bat_iv_ogm.c:1714 process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3236 process_scheduled_works kernel/workqueue.c:3319 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400 kthread+0x3c2/0x780 kernel/kthread.c:463 ret_from_fork+0x56a/0x730 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 rcu: rcu_preempt kthread starved for 7048 jiffies! g80661 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:28096 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x1190/0x5de0 kernel/sched/core.c:6961 __schedule_loop kernel/sched/core.c:7043 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:7058 schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x1ea/0xb00 kernel/rcu/tree.c:2083 rcu_gp_kthread+0x270/0x380 kernel/rcu/tree.c:2285 kthread+0x3c2/0x780 kernel/kthread.c:463 ret_from_fork+0x56a/0x730 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 rcu: Stack dump where RCU GP kthread last ran: Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:82 Code: 6d 61 02 c3 cc cc cc cc 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d d3 46 15 00 fb f4 cc 09 03 00 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90 RSP: 0018:ffffc90000197df8 EFLAGS: 000002c2 RAX: 00000000051ffb93 RBX: 0000000000000001 RCX: ffffffff8b94cb49 RDX: 0000000000000000 RSI: ffffffff8de52cd1 RDI: ffffffff8c163400 RBP: ffffed1003cdf488 R08: 0000000000000001 R09: ffffed10170a6655 R10: ffff8880b85332ab R11: 0000000000000000 R12: 0000000000000001 R13: ffff88801e6fa440 R14: ffffffff90ab7590 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8881247b2000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055ffcf52abe0 CR3: 0000000033f9b000 CR4: 00000000003526f0 Call Trace: arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline] default_idle+0x13/0x20 arch/x86/kernel/process.c:757 default_idle_call+0x6d/0xb0 kernel/sched/idle.c:122 cpuidle_idle_call kernel/sched/idle.c:190 [inline] do_idle+0x391/0x510 kernel/sched/idle.c:330 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:428 start_secondary+0x21d/0x2b0 arch/x86/kernel/smpboot.c:315 common_startup_64+0x13e/0x148