rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P3809/1:b..l (detected by 0, t=10502 jiffies, g=16357, q=137 ncpus=2) task:kworker/u4:9 state:R running task stack:25592 pid:3809 ppid:2 flags:0x00004000 Workqueue: bat_events batadv_iv_send_outstanding_bat_ogm_packet Call Trace: context_switch kernel/sched/core.c:5241 [inline] __schedule+0x143f/0x4570 kernel/sched/core.c:6558 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6870 irqentry_exit+0x53/0x80 kernel/entry/common.c:439 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:653 RIP: 0010:__rcu_read_unlock+0x0/0x100 kernel/rcu/tree_plugin.h:419 Code: 96 f9 6d 00 eb b1 44 89 f9 80 e1 07 80 c1 03 38 c1 7c b0 4c 89 ff e8 0f f9 6d 00 eb a6 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 <55> 41 57 41 56 41 55 41 54 53 49 bc 00 00 00 00 00 fc ff df 65 4c RSP: 0018:ffffc90004767a58 EFLAGS: 00000293 RAX: ffffffff8a727672 RBX: 0000000000000001 RCX: ffff8880271ed940 RDX: 0000000000000000 RSI: ffffffff8b5d69a0 RDI: ffffffff8b5d6960 RBP: ffffc90004767b98 R08: ffffffff8a727660 R09: fffffbfff223b645 R10: 0000000000000000 R11: dffffc0000000001 R12: ffff8880766c3800 R13: ffff888058fb0a80 R14: dffffc0000000000 R15: ffff888024935498 rcu_read_unlock include/linux/rcupdate.h:823 [inline] batadv_iv_ogm_slide_own_bcast_window net/batman-adv/bat_iv_ogm.c:772 [inline] batadv_iv_ogm_schedule_buff net/batman-adv/bat_iv_ogm.c:826 [inline] batadv_iv_ogm_schedule+0x6e3/0x1090 net/batman-adv/bat_iv_ogm.c:869 batadv_iv_send_outstanding_bat_ogm_packet+0x6fa/0x800 net/batman-adv/bat_iv_ogm.c:1713 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439 kthread+0x28d/0x320 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 rcu: rcu_preempt kthread starved for 10493 jiffies! g16357 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:26752 pid:16 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5241 [inline] __schedule+0x143f/0x4570 kernel/sched/core.c:6558 schedule+0xbf/0x180 kernel/sched/core.c:6634 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1965 rcu_gp_fqs_loop+0x2d2/0x1150 kernel/rcu/tree.c:1706 rcu_gp_kthread+0xa3/0x3b0 kernel/rcu/tree.c:1905 kthread+0x28d/0x320 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: Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline] NMI backtrace for cpu 1 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline] NMI backtrace for cpu 1 skipped: idling at acpi_safe_halt drivers/acpi/processor_idle.c:111 [inline] NMI backtrace for cpu 1 skipped: idling at acpi_idle_do_entry+0x10f/0x340 drivers/acpi/processor_idle.c:567