rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P4326/1:b..l (detected by 1, t=10503 jiffies, g=14893, q=51 ncpus=2) task:kworker/u4:5 state:R running task stack:21960 pid:4326 ppid:2 flags:0x00004000 Workqueue: bat_events batadv_iv_send_outstanding_bat_ogm_packet Call Trace: context_switch kernel/sched/core.c:5244 [inline] __schedule+0x10e9/0x40d0 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:ffffc900049e7920 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 0000000000000000 RCX: 0129eec390951500 RDX: 0000000000000000 RSI: ffffffff8a6c1160 RDI: ffffffff8abf14a0 RBP: ffffc900049e7a28 R08: dffffc0000000000 R09: fffffbfff2117249 R10: fffffbfff2117249 R11: 1ffffffff2117248 R12: 0000000000000001 R13: 1ffff9200093cf30 R14: 0000000000000246 R15: dffffc0000000000 rcu_lock_acquire include/linux/rcupdate.h:350 [inline] rcu_read_lock include/linux/rcupdate.h:791 [inline] batadv_iv_ogm_slide_own_bcast_window net/batman-adv/bat_iv_ogm.c:754 [inline] batadv_iv_ogm_schedule_buff net/batman-adv/bat_iv_ogm.c:825 [inline] batadv_iv_ogm_schedule+0x413/0xe90 net/batman-adv/bat_iv_ogm.c:868 batadv_iv_send_outstanding_bat_ogm_packet+0x72d/0x840 net/batman-adv/bat_iv_ogm.c:1712 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 rcu: rcu_preempt kthread starved for 10528 jiffies! g14893 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:27840 pid:16 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5244 [inline] __schedule+0x10e9/0x40d0 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_reschedule_ipi+0x16/0x20 arch/x86/include/asm/idtentry.h:696 RIP: 0010:__free_object+0x90b/0x9d0 lib/debugobjects.c:416 Code: fd 48 c7 84 24 a0 00 00 00 00 00 00 00 9c 8f 84 24 a0 00 00 00 f6 84 24 a1 00 00 00 02 75 55 f7 44 24 18 00 02 00 00 74 01 fb <48> c7 44 24 60 0e 36 e0 45 48 8b 44 24 38 4a c7 04 28 00 00 00 00 RSP: 0018:ffffc90000157980 EFLAGS: 00000206 RAX: 11fc3b9e3f557f00 RBX: ffff8880b8f37628 RCX: 11fc3b9e3f557f00 RDX: dffffc0000000000 RSI: ffffffff8a6bffe0 RDI: ffffffff8abf14a0 RBP: ffffc90000157b60 R08: dffffc0000000000 R09: ffffc90000157a60 R10: fffff5200002af5c R11: 1ffff9200002af4c R12: ffff8880b8f37630 R13: dffffc0000000000 R14: 1ffff110171e6ec5 R15: ffff88807e63cc10 free_object lib/debugobjects.c:424 [inline] debug_object_free+0x2a2/0x3e0 lib/debugobjects.c:856 destroy_timer_on_stack kernel/time/timer.c:812 [inline] schedule_timeout+0x173/0x280 kernel/time/timer.c:1969 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 rcu: Stack dump where RCU GP kthread last ran: CPU: 1 PID: 0 Comm: swapper/1 Not tainted 6.1.142-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:default_idle+0xb/0x10 arch/x86/kernel/process.c:742 Code: 48 89 df e8 07 98 b8 f7 e9 4c ff ff ff e8 bd 15 f6 ff 00 00 cc cc 00 00 cc cc 00 00 cc cc 00 66 90 0f 00 2d d7 e3 4c 00 fb f4 0f 1f 40 00 41 57 41 56 53 49 be 00 00 00 00 00 fc ff df 65 48 RSP: 0018:ffffc90000177de8 EFLAGS: 000002c6 RAX: 3285aa7159167600 RBX: ffffffff8a19bfb7 RCX: 3285aa7159167600 RDX: 0000000000000001 RSI: ffffffff8a6bffe0 RDI: ffffffff8abf14a0 RBP: ffffc90000177f20 R08: dffffc0000000000 R09: ffffed10171e6af6 R10: ffffed10171e6af6 R11: 1ffff110171e6af5 R12: 0000000000000001 R13: dffffc0000000000 R14: ffff88813fef1dc0 R15: 1ffffffff1bfd1e6 FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c3e86de CR3: 000000005b74c000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: default_idle_call+0x84/0xc0 kernel/sched/idle.c:109 cpuidle_idle_call kernel/sched/idle.c:191 [inline] do_idle+0x1fc/0x570 kernel/sched/idle.c:303 cpu_startup_entry+0x3f/0x60 kernel/sched/idle.c:401 start_secondary+0xe4/0xf0 arch/x86/kernel/smpboot.c:281 secondary_startup_64_no_verify+0xcf/0xdb