rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
	(detected by 0, t=10502 jiffies, g=7153, q=89)
rcu: All QSes seen, last rcu_preempt kthread activity 10503 (4294954365-4294943862), jiffies_till_next_fqs=1, root ->qsmask 0x0
udevd           R  running task    24224  4087      1 0x0000400a
Call Trace:
 <IRQ>
 sched_show_task+0x40f/0x560 kernel/sched/core.c:5954
 print_other_cpu_stall kernel/rcu/tree_stall.h:410 [inline]
 check_cpu_stall kernel/rcu/tree_stall.h:538 [inline]
 rcu_pending kernel/rcu/tree.c:2827 [inline]
 rcu_sched_clock_irq+0x1861/0x1ad0 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:1517 [inline]
 __hrtimer_run_queues+0x403/0x840 kernel/time/hrtimer.c:1579
 hrtimer_interrupt+0x38c/0xda0 kernel/time/hrtimer.c:1641
 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:free_thread_stack+0x182/0x590 kernel/fork.c:284
Code: a0 69 00 48 8b 3b be fc ff ff ff e8 28 04 00 00 43 80 3c 2e 00 74 08 4c 89 e7 e8 09 a0 69 00 49 8b 1c 24 48 83 c3 08 48 89 d8 <48> c1 e8 03 42 80 3c 28 00 74 08 48 89 df e8 eb 9f 69 00 48 8b 1b
RSP: 0018:ffffc900017e7b10 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff13
RAX: ffff88808c66ee88 RBX: ffff88808c66ee88 RCX: ffff888094fee2c0
RDX: 0000000000000000 RSI: 00000000fffffffc RDI: ffffea000252f400
RBP: ffffc900017e7b48 R08: 000000000003a728 R09: ffffed10149212a7
R10: ffffed10149212a7 R11: 0000000000000000 R12: ffff88808c66ef20
R13: dffffc0000000000 R14: 1ffff110118cdde4 R15: ffff8880a4909528
 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
 schedule+0x181/0x210 kernel/sched/core.c:4155
 schedule_hrtimeout_range_clock+0x108/0x510 kernel/time/hrtimer.c:2121
 schedule_hrtimeout_range+0x2a/0x40 kernel/time/hrtimer.c:2175
 ep_poll+0xa4d/0xe80 fs/eventpoll.c:1915
 do_epoll_wait+0x1ee/0x260 fs/eventpoll.c:2294
 __do_sys_epoll_wait fs/eventpoll.c:2304 [inline]
 __se_sys_epoll_wait fs/eventpoll.c:2301 [inline]
 __x64_sys_epoll_wait+0x9a/0xb0 fs/eventpoll.c:2301
 do_syscall_64+0xf7/0x1c0 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7f3e219f9943
Code: 00 31 d2 48 29 c2 64 89 11 48 83 c8 ff eb ea 90 90 90 90 90 90 90 90 83 3d b5 dc 2a 00 00 75 13 49 89 ca b8 e8 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 34 c3 48 83 ec 08 e8 3b c4 00 00 48 89 04 24
RSP: 002b:00007fffc158d2d8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e8
RAX: ffffffffffffffda RBX: 00000000ffffffff RCX: 00007f3e219f9943
RDX: 0000000000000008 RSI: 00007fffc158d3d0 RDI: 000000000000000a
RBP: 0000000001414b40 R08: 0000000000000000 R09: 0000000000000001
R10: 00000000ffffffff R11: 0000000000000246 R12: 0000000000000003
R13: 0000000000000010 R14: 000000000142c900 R15: 0000000001413250
rcu: rcu_preempt kthread starved for 10533 jiffies! g7153 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
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