rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	1-...!: (1 ticks this GP) idle=49e/1/0x4000000000000002 softirq=44865/44869 fqs=0 
rcu: 	 (t=11105 jiffies g=48989 q=50)
rcu: rcu_preempt kthread starved for 11105 jiffies! g48989 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0
rcu: RCU grace-period kthread stack dump:
rcu_preempt     R  running task    22736    10      2 0x80000000
Call Trace:
 context_switch kernel/sched/core.c:2825 [inline]
 __schedule+0x86c/0x1ed0 kernel/sched/core.c:3473
 schedule+0xfe/0x460 kernel/sched/core.c:3517
 schedule_timeout+0x140/0x260 kernel/time/timer.c:1804
 rcu_gp_kthread+0x9d9/0x2310 kernel/rcu/tree.c:2194
 kthread+0x35a/0x420 kernel/kthread.c:246
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:413
NMI backtrace for cpu 1
CPU: 1 PID: 5522 Comm: kworker/1:3 Not tainted 4.19.0-rc6+ #165
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: rcu_gp process_srcu
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1c4/0x2b4 lib/dump_stack.c:113
 nmi_cpu_backtrace.cold.3+0x63/0xa2 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x1b3/0x1ed lib/nmi_backtrace.c:62
 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38
 trigger_single_cpu_backtrace include/linux/nmi.h:162 [inline]
 rcu_dump_cpu_stacks+0x175/0x1c2 kernel/rcu/tree.c:1340
 print_cpu_stall.cold.78+0x2d3/0x524 kernel/rcu/tree.c:1478
 check_cpu_stall kernel/rcu/tree.c:1550 [inline]
 __rcu_pending kernel/rcu/tree.c:3276 [inline]
 rcu_pending kernel/rcu/tree.c:3319 [inline]
 rcu_check_callbacks+0xfd9/0x1990 kernel/rcu/tree.c:2665
 update_process_times+0x2d/0x70 kernel/time/timer.c:1636
 tick_sched_handle+0x9f/0x180 kernel/time/tick-sched.c:164
 tick_sched_timer+0x45/0x130 kernel/time/tick-sched.c:1274
 __run_hrtimer kernel/time/hrtimer.c:1398 [inline]
 __hrtimer_run_queues+0x41c/0x10d0 kernel/time/hrtimer.c:1460
 hrtimer_interrupt+0x313/0x780 kernel/time/hrtimer.c:1518
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1029 [inline]
 smp_apic_timer_interrupt+0x1a1/0x760 arch/x86/kernel/apic/apic.c:1054
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:864
 </IRQ>
RIP: 0010:check_preemption_disabled+0x0/0x200
Code: a6 ed 34 fe e9 5d eb ff ff e8 9c ed 34 fe e9 2f f3 ff ff e8 32 ee 34 fe e9 5d ec ff ff e8 28 ee 34 fe e9 26 ec ff ff 90 90 90 <55> 48 89 e5 41 57 41 56 49 89 f6 41 55 49 89 fd 41 54 53 48 83 ec
RSP: 0018:ffff880193067110 EFLAGS: 00000293 ORIG_RAX: ffffffffffffff13
RAX: ffff88019304e580 RBX: 00000102a6cb210e RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff884090c0 RDI: ffffffff88409100
RBP: ffff880193067118 R08: ffff88019304e580 R09: 1ffffd1ffffa0a80
R10: ffff880193067250 R11: ffffffff8aefcf67 R12: 00000102a6cb17a3
R13: 0000000000002ced R14: 0000000000000001 R15: ffffffff8aefcbc0
 delay_tsc+0x42/0xc0 arch/x86/lib/delay.c:79
 __delay arch/x86/lib/delay.c:161 [inline]
 __const_udelay+0x62/0x80 arch/x86/lib/delay.c:175
 try_check_zero+0x384/0x5f0 kernel/rcu/srcutree.c:721
 srcu_advance_state kernel/rcu/srcutree.c:1155 [inline]
 process_srcu+0x6bf/0x1460 kernel/rcu/srcutree.c:1249
 process_one_work+0xc90/0x1b90 kernel/workqueue.c:2153
 worker_thread+0x17f/0x1390 kernel/workqueue.c:2296
 kthread+0x35a/0x420 kernel/kthread.c:246
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:413