rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P7 (detected by 1, t=10503 jiffies, g=6053, q=258) kworker/u4:0 R running task 27512 7 2 0x80004008 Workqueue: bat_events batadv_nc_worker Call Trace: 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 RIP: 0010:__memcg_kmem_uncharge+0xd/0x2e0 mm/memcontrol.c:2909 Code: 81 c3 08 02 00 00 48 89 df 4c 89 f6 e8 dc 7d ff ff 5b 41 5e 5d c3 0f 1f 80 00 00 00 00 55 48 89 e5 41 57 41 56 41 55 41 54 53 <50> 89 f3 49 89 fc 48 b8 00 00 00 00 00 fc ff df 4c 8d 77 38 4d 89 RSP: 0018:ffffc90000cdf970 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 RAX: ffffffff81486ea4 RBX: ffffea00028a2dc0 RCX: ffff8880a9d9e1c0 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffea00028a2dc0 RBP: ffffc90000cdf998 R08: 000000000003a768 R09: ffffed10131ec70f R10: ffffed10131ec70f R11: 0000000000000000 R12: ffff8880a2fb9820 R13: dffffc0000000000 R14: 1ffff110145f7304 R15: ffff888098f63868 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_irq+0xc1/0x140 kernel/sched/core.c:4338 retint_kernel+0x1b/0x2b RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:752 [inline] RIP: 0010:lock_acquire+0x1b2/0x250 kernel/locking/lockdep.c:4488 Code: c1 e8 03 42 80 3c 30 00 74 0c 48 c7 c7 28 96 0a 89 e8 b2 7e 56 00 48 83 3d d2 01 af 07 00 0f 84 9c 00 00 00 48 8b 7d c0 57 9d <0f> 1f 44 00 00 48 83 c4 30 5b 41 5c 41 5d 41 5e 41 5f 5d c3 44 89 RSP: 0018:ffffc90000cdfbf8 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff13 RAX: 1ffffffff12152c5 RBX: 0000000000000000 RCX: 9dc97db76c8fae17 RDX: dffffc0000000000 RSI: ffff8880a9d9eaa8 RDI: 0000000000000286 RBP: ffffc90000cdfc50 R08: dffffc0000000000 R09: fffffbfff13c851d R10: fffffbfff13c851d R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: dffffc0000000000 R15: ffffffff890d4bc0 rcu_lock_acquire+0x2e/0x40 include/linux/rcupdate.h:208 rcu_read_lock include/linux/rcupdate.h:617 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:407 [inline] batadv_nc_worker+0xdc/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 10517 jiffies! g6053 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0 rcu: RCU grace-period kthread stack dump: rcu_preempt R running task 29032 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