rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P24667/1:b..l rcu: (detected by 1, t=10502 jiffies, g=86413, q=86 ncpus=2) task:kworker/u8:21 state:R running task stack:25864 pid:24667 tgid:24667 ppid:2 task_flags:0x4208060 flags:0x00004000 Workqueue: bat_events batadv_nc_worker 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_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:707 RIP: 0010:lock_acquire+0x62/0x350 kernel/locking/lockdep.c:5872 Code: b8 3d 12 83 f8 07 0f 87 bc 02 00 00 89 c0 48 0f a3 05 22 0a 13 0f 0f 82 74 02 00 00 8b 35 ea 3b 13 0f 85 f6 0f 85 8d 00 00 00 <48> 8b 44 24 30 65 48 2b 05 79 b8 3d 12 0f 85 c7 02 00 00 48 83 c4 RSP: 0018:ffffc90021b77a40 EFLAGS: 00000206 RAX: 0000000000000046 RBX: ffffffff8e5c1120 RCX: 00000000a0ddb310 RDX: 0000000000000000 RSI: ffffffff8de27535 RDI: ffffffff8c15fb80 RBP: 0000000000000002 R08: 2b9fae8fdf9cd17f R09: 0000000000000000 R10: 0000000000000002 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:841 [inline] batadv_nc_process_nc_paths.part.0+0xe4/0x3e0 net/batman-adv/network-coding.c:687 batadv_nc_process_nc_paths net/batman-adv/network-coding.c:679 [inline] batadv_nc_worker+0xcd3/0x1030 net/batman-adv/network-coding.c:728 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+0x3c5/0x780 kernel/kthread.c:464 ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g86413 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=0 timer-softirq=68942 rcu: rcu_preempt kthread starved for 10502 jiffies! g86413 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I 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+0x3c5/0x780 kernel/kthread.c:464 ret_from_fork+0x5d7/0x6f0 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 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 26328 Comm: syz.3.2954 Not tainted 6.16.0-syzkaller-11105-ga6923c06a3b2 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:debug_object_deactivate+0x140/0x3a0 lib/debugobjects.c:875 Code: 48 c1 e3 03 48 8d 93 c8 16 fd 9a 4c 8d a3 c0 16 fd 9a 48 89 d7 48 89 54 24 08 e8 3b 35 ab 06 48 8b 54 24 08 48 89 c1 4c 89 e0 <48> c1 e8 03 42 80 3c 28 00 0f 85 da 01 00 00 48 8b 9b c0 16 fd 9a RSP: 0018:ffffc90000007d50 EFLAGS: 00000096 RAX: ffffffff9b04bb68 RBX: 000000000007a4a8 RCX: 0000000000000002 RDX: ffffffff9b04bb70 RSI: 0000000000000004 RDI: ffffc90000007cc0 RBP: ffffc90000007e30 R08: 0000000000000001 R09: fffff52000000f98 R10: 0000000000000003 R11: 0000000000000000 R12: ffffffff9b04bb68 R13: dffffc0000000000 R14: ffff888079957340 R15: 1ffff92000000fac FS: 000055557f4f8500(0000) GS:ffff8881246c8000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c34d543 CR3: 000000005c60d000 CR4: 00000000003526f0 Call Trace: debug_hrtimer_deactivate kernel/time/hrtimer.c:450 [inline] debug_deactivate kernel/time/hrtimer.c:490 [inline] __run_hrtimer kernel/time/hrtimer.c:1729 [inline] __hrtimer_run_queues+0x46f/0xad0 kernel/time/hrtimer.c:1825 hrtimer_interrupt+0x397/0x8e0 kernel/time/hrtimer.c:1887 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1039 [inline] __sysvec_apic_timer_interrupt+0x10b/0x3f0 arch/x86/kernel/apic/apic.c:1056 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline] sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1050 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:stack_depot_save_flags+0xf/0xa40 lib/stackdepot.c:588 Code: e9 07 ff ff ff 66 0f 1f 44 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 83 f9 03 0f 87 90 03 00 00 41 57 <41> 56 49 89 fe 41 55 41 54 41 89 d4 55 89 cd 53 48 83 ec 30 e8 58 RSP: 0018:ffffc9002152f950 EFLAGS: 00000293 RAX: 000000000000000f RBX: ffffc9002152f960 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 000000000000000f RDI: ffffc9002152f960 RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: ffff88805d2e3248 R15: ffffffff8ce3e560 kasan_save_stack+0x42/0x60 mm/kasan/common.c:48 kasan_record_aux_stack+0xa7/0xc0 mm/kasan/generic.c:548 __call_rcu_common.constprop.0+0xa5/0xa10 kernel/rcu/tree.c:3123 destroy_inode+0x12c/0x1b0 fs/inode.c:401 evict+0x5b4/0x920 fs/inode.c:834 iput_final fs/inode.c:1897 [inline] iput fs/inode.c:1923 [inline] iput+0x521/0x880 fs/inode.c:1909 dentry_unlink_inode+0x29c/0x480 fs/dcache.c:466 __dentry_kill+0x1d0/0x600 fs/dcache.c:669 dput.part.0+0x4b1/0x9b0 fs/dcache.c:911 dput+0x1f/0x30 fs/dcache.c:901 __fput+0x51c/0xb70 fs/file_table.c:476 task_work_run+0x150/0x240 kernel/task_work.c:227 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop+0xeb/0x110 kernel/entry/common.c:43 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline] do_syscall_64+0x3f6/0x4c0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f442258eb69 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fff09713fd8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00000000000f1fa8 RCX: 00007f442258eb69 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007f44227b7ba0 R08: 0000000000000001 R09: 0000001e097142cf R10: 00007f4422400000 R11: 0000000000000246 R12: 00007f44227b5fac R13: 00007f44227b5fa0 R14: ffffffffffffffff R15: 00007fff097140f0