rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P347
	(detected by 1, t=10503 jiffies, g=6521, q=220)
kworker/u4:5    R  running task    26640   347      2 0x80004008
Workqueue: bat_events batadv_nc_worker
Call Trace:
 <IRQ>
 sched_show_task+0x40f/0x560 kernel/sched/core.c:5954
 rcu_print_detail_task_stall_rnp kernel/rcu/tree_stall.h:190 [inline]
 print_other_cpu_stall kernel/rcu/tree_stall.h:398 [inline]
 check_cpu_stall kernel/rcu/tree_stall.h:538 [inline]
 rcu_pending kernel/rcu/tree.c:2827 [inline]
 rcu_sched_clock_irq+0x16b1/0x1ad0 kernel/rcu/tree.c:2271
 update_process_times+0x12d/0x180 kernel/time/timer.c:1726
 tick_sched_handle kernel/time/tick-sched.c:167 [inline]
 tick_sched_timer+0x263/0x420 kernel/time/tick-sched.c:1310
 __run_hrtimer kernel/time/hrtimer.c:1514 [inline]
 __hrtimer_run_queues+0x403/0x840 kernel/time/hrtimer.c:1576
 hrtimer_interrupt+0x38c/0xda0 kernel/time/hrtimer.c:1638
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1110 [inline]
 smp_apic_timer_interrupt+0x109/0x280 arch/x86/kernel/apic/apic.c:1135
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829
 </IRQ>
RIP: 0010:__memcg_kmem_uncharge+0x219/0x2e0 mm/memcontrol.c:2925
Code: 4b 0d 89 e8 59 97 00 00 bf 01 00 00 00 e8 2f e3 9b ff 65 8b 05 d4 fd 4a 7e 85 c0 74 53 48 83 c4 08 5b 41 5c 41 5d 41 5e 41 5f <5d> c3 49 8d 5f 10 48 89 df be 08 00 00 00 e8 04 c1 fa ff 48 8b 45
RSP: 0018:ffffc90002107a50 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000001 RBX: ffffea0002433480 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffea0002433480
RBP: ffffc90002107a50 R08: 000000000003a768 R09: ffffed1014eb62df
R10: ffffed1014eb62df R11: 0000000000000000 R12: ffff8880a77207a0
R13: dffffc0000000000 R14: 1ffff11014ee40f4 R15: ffff8880a75b16e8
 memcg_kmem_uncharge include/linux/memcontrol.h:1402 [inline]
 free_thread_stack+0x12e/0x590 kernel/fork.c:284
 release_task_stack kernel/fork.c:440 [inline]
 put_task_stack+0xa3/0x130 kernel/fork.c:451
 finish_task_switch+0x3f1/0x550 kernel/sched/core.c:3256
 context_switch kernel/sched/core.c:3388 [inline]
 __schedule+0x9a8/0xcc0 kernel/sched/core.c:4081
 preempt_schedule_notrace+0xdb/0x120 kernel/sched/core.c:4309
 ___preempt_schedule_notrace+0x16/0x27 arch/x86/entry/thunk_64.S:51
 rcu_is_watching+0x82/0xa0 kernel/rcu/tree.c:923
 rcu_read_lock include/linux/rcupdate.h:618 [inline]
 batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:407 [inline]
 batadv_nc_worker+0x115/0x600 net/batman-adv/network-coding.c:718
 process_one_work+0x7ef/0x10d0 kernel/workqueue.c:2264
 worker_thread+0xc01/0x1630 kernel/workqueue.c:2410
 kthread+0x332/0x350 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
rcu: rcu_preempt kthread starved for 10518 jiffies! g6521 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0
rcu: RCU grace-period kthread stack dump:
rcu_preempt     R  running task    29104    10      2 0x80004000
Call Trace:
 context_switch kernel/sched/core.c:3385 [inline]
 __schedule+0x9a0/0xcc0 kernel/sched/core.c:4081
 schedule+0x181/0x210 kernel/sched/core.c:4155
 schedule_timeout+0x14f/0x240 kernel/time/timer.c:1895
 rcu_gp_fqs_loop kernel/rcu/tree.c:1661 [inline]
 rcu_gp_kthread+0xed8/0x1770 kernel/rcu/tree.c:1821
 kthread+0x332/0x350 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352