rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P30876/1:b..l rcu: (detected by 0, t=10503 jiffies, g=165973, q=118 ncpus=2) task:kworker/u4:11 state:R running task stack:25680 pid:30876 tgid:30876 ppid:2 flags:0x00004000 Workqueue: bat_events batadv_nc_worker Call Trace: context_switch kernel/sched/core.c:5376 [inline] __schedule+0xedb/0x5af0 kernel/sched/core.c:6688 preempt_schedule_irq+0x52/0x90 kernel/sched/core.c:7008 irqentry_exit+0x36/0x80 kernel/entry/common.c:432 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645 RIP: 0010:lock_acquire+0x1ef/0x520 kernel/locking/lockdep.c:5722 Code: c1 05 bd 6c 9a 7e 83 f8 01 0f 85 b4 02 00 00 9c 58 f6 c4 02 0f 85 9f 02 00 00 48 85 ed 74 01 fb 48 b8 00 00 00 00 00 fc ff df <48> 01 c3 48 c7 03 00 00 00 00 48 c7 43 08 00 00 00 00 48 8b 84 24 RSP: 0018:ffffc900032bfac8 EFLAGS: 00000206 RAX: dffffc0000000000 RBX: 1ffff92000657f5b RCX: 000000006373687c RDX: 0000000000000001 RSI: ffffffff8accbae0 RDI: ffffffff8b2f0e80 RBP: 0000000000000200 R08: 0000000000000000 R09: fffffbfff23e35d0 R10: ffffffff91f1ae87 R11: 0000000000000002 R12: 0000000000000000 R13: 0000000000000000 R14: ffffffff8cfabbe0 R15: 0000000000000000 rcu_lock_acquire include/linux/rcupdate.h:301 [inline] rcu_read_lock include/linux/rcupdate.h:747 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline] batadv_nc_worker+0x16e/0x10e0 net/batman-adv/network-coding.c:719 process_one_work+0x886/0x15d0 kernel/workqueue.c:2630 process_scheduled_works kernel/workqueue.c:2703 [inline] worker_thread+0x8b9/0x1290 kernel/workqueue.c:2784 kthread+0x2c6/0x3a0 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242 rcu: rcu_preempt kthread starved for 10527 jiffies! g165973 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:27696 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5376 [inline] __schedule+0xedb/0x5af0 kernel/sched/core.c:6688 __schedule_loop kernel/sched/core.c:6763 [inline] schedule+0xe9/0x270 kernel/sched/core.c:6778 schedule_timeout+0x137/0x290 kernel/time/timer.c:2167 rcu_gp_fqs_loop+0x1ec/0xb10 kernel/rcu/tree.c:1631 rcu_gp_kthread+0x24b/0x380 kernel/rcu/tree.c:1830 kthread+0x2c6/0x3a0 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242 rcu: Stack dump where RCU GP kthread last ran: CPU: 0 PID: 13636 Comm: syz-executor.4 Not tainted 6.7.0-rc3-syzkaller-00134-g994d5c58e50e #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023 RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline] RIP: 0010:_raw_spin_unlock_irq+0x29/0x50 kernel/locking/spinlock.c:202 Code: 90 f3 0f 1e fa 53 48 8b 74 24 08 48 89 fb 48 83 c7 18 e8 4a c7 e4 f6 48 89 df e8 b2 3e e5 f6 e8 fd fd 0a f7 fb bf 01 00 00 00 d2 f7 d6 f6 65 8b 05 a3 77 80 75 85 c0 74 02 5b c3 e8 70 3b 7d RSP: 0018:ffffc9000ef17d00 EFLAGS: 00000206 RAX: 0000000003bc330f RBX: ffff88807444ef00 RCX: 1ffffffff1e320e9 RDX: 0000000000000000 RSI: ffffffff8accb7e0 RDI: 0000000000000001 RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000001 R10: ffffffff8f1939d7 R11: 0000000000000000 R12: ffff88807444f398 R13: 0000000000000021 R14: ffff88807444f300 R15: 1ffff92001de2faf FS: 0000555557004480(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f588d3f9f00 CR3: 0000000059696000 CR4: 0000000000350ef0 Call Trace: spin_unlock_irq include/linux/spinlock.h:401 [inline] get_signal+0x1899/0x2790 kernel/signal.c:2907 arch_do_signal_or_restart+0x90/0x7f0 arch/x86/kernel/signal.c:309 exit_to_user_mode_loop kernel/entry/common.c:168 [inline] exit_to_user_mode_prepare+0x121/0x240 kernel/entry/common.c:204 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline] syscall_exit_to_user_mode+0x1e/0x60 kernel/entry/common.c:296 do_syscall_64+0x4d/0x110 arch/x86/entry/common.c:88 entry_SYSCALL_64_after_hwframe+0x63/0x6b RIP: 0033:0x7f588c67cae9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 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 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fff2cb7cd28 EFLAGS: 00000246 RAX: fffffffffffffffc RBX: 0000000000293fbf RCX: 00007f588c67cae9 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f588c79bf8c RBP: 0000000000000032 R08: 00007f588c79bf8c R09: 00007f588c79bf8c R10: 00007fff2cb7ce60 R11: 0000000000000246 R12: 00007f588c79bf8c R13: 0000000000293ff1 R14: 00007fff2cb7ce80 R15: 00007fff2cb7ce60