rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	1-...!: (1 ticks this GP) idle=f02/1/0x4000000000000004 softirq=31991/31991 fqs=0 
rcu: 	 (t=29940 jiffies g=45057 q=172)
rcu: rcu_preempt kthread starved for 29940 jiffies! g45057 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=1
rcu: RCU grace-period kthread stack dump:
rcu_preempt     I26200    10      2 0x80000000
Call Trace:
 context_switch kernel/sched/core.c:2831 [inline]
 __schedule+0x897/0x1e60 kernel/sched/core.c:3472
 schedule+0xfe/0x350 kernel/sched/core.c:3516
 schedule_timeout+0x14a/0x250 kernel/time/timer.c:1803
 rcu_gp_fqs_loop+0x6ba/0x970 kernel/rcu/tree.c:1948
 rcu_gp_kthread+0x2bb/0xc10 kernel/rcu/tree.c:2105
 kthread+0x357/0x430 kernel/kthread.c:246
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352
NMI backtrace for cpu 1
CPU: 1 PID: 8142 Comm: kworker/1:3 Not tainted 5.0.0-rc1+ #14
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+0x1db/0x2d0 lib/dump_stack.c:113
 nmi_cpu_backtrace.cold+0x63/0xa4 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x1be/0x236 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:164 [inline]
 rcu_dump_cpu_stacks+0x183/0x1cf kernel/rcu/tree.c:1211
 print_cpu_stall.cold+0x227/0x40c kernel/rcu/tree.c:1348
 check_cpu_stall kernel/rcu/tree.c:1422 [inline]
 rcu_pending kernel/rcu/tree.c:3018 [inline]
 rcu_check_callbacks+0xb32/0x1380 kernel/rcu/tree.c:2521
 update_process_times+0x32/0x80 kernel/time/timer.c:1635
 tick_sched_handle+0xa2/0x190 kernel/time/tick-sched.c:161
 tick_sched_timer+0x47/0x130 kernel/time/tick-sched.c:1271
 __run_hrtimer kernel/time/hrtimer.c:1389 [inline]
 __hrtimer_run_queues+0x3a7/0x1050 kernel/time/hrtimer.c:1451
 hrtimer_interrupt+0x314/0x770 kernel/time/hrtimer.c:1509
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1035 [inline]
 smp_apic_timer_interrupt+0x18d/0x760 arch/x86/kernel/apic/apic.c:1060
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:807
RIP: 0010:trace_softirq_entry include/trace/events/irq.h:128 [inline]
RIP: 0010:__do_softirq+0x2b0/0xb11 kernel/softirq.c:291
Code: c7 c0 00 80 92 89 48 c1 e8 03 42 80 3c 38 00 0f 85 20 08 00 00 48 83 3d 5d 7d 72 01 00 0f 84 08 07 00 00 fb 66 0f 1f 44 00 00 <48> 8d 55 98 b8 ff ff ff ff 48 c7 85 e8 fe ff ff 00 91 80 89 48 c1
RSP: 0018:ffff8880ae707e20 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13
RAX: 1ffffffff1325000 RBX: ffff88809e08e4c0 RCX: 1ffff11013c11db6
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88809e08ed3c
RBP: ffff8880ae707f98 R08: 0000000000000002 R09: ffff88809e08edb0
R10: ffff88809e08e4c0 R11: 0000000000000000 R12: ffff888093a4f4f8
R13: 0000000000000025 R14: 0000000000000025 R15: dffffc0000000000
 invoke_softirq kernel/softirq.c:373 [inline]
 irq_exit+0x180/0x1d0 kernel/softirq.c:413
 exiting_irq arch/x86/include/asm/apic.h:536 [inline]
 do_IRQ+0x114/0x1d0 arch/x86/kernel/irq.c:258
 common_interrupt+0xf/0xf arch/x86/entry/entry_64.S:583
 </IRQ>
RIP: 0010:rdtsc arch/x86/include/asm/msr.h:207 [inline]
RIP: 0010:rdtsc_ordered arch/x86/include/asm/msr.h:232 [inline]
RIP: 0010:delay_tsc+0x4c/0xc0 arch/x86/lib/delay.c:61
Code: e8 0f 31 48 c1 e2 20 48 09 c2 49 89 d4 eb 16 f3 90 bf 01 00 00 00 e8 d3 04 67 f9 e8 ae a6 9f fb 44 39 e8 75 36 0f ae e8 0f 31 <48> c1 e2 20 48 89 d3 48 09 c3 48 89 d8 4c 29 e0 4c 39 f0 73 24 bf
RSP: 0018:ffff888093a4f5a0 EFLAGS: 00000246 ORIG_RAX: ffffffffffffffda
RAX: 000000006622007b RBX: 000001a06621ffdd RCX: ffffffff8390df9a
RDX: 00000000000001a0 RSI: ffffffff8390dfa8 RDI: 0000000000000005
RBP: ffff888093a4f5c0 R08: ffff88809e08e4c0 R09: fffffbfff1348171
R10: ffff888093a4f710 R11: ffffffff89a40b87 R12: 000001a06621f7b0
R13: 0000000000000001 R14: 0000000000002ced R15: ffffffff89a407e0
 __delay arch/x86/lib/delay.c:161 [inline]
 __const_udelay+0x5f/0x80 arch/x86/lib/delay.c:175
 try_check_zero+0x352/0x5c0 kernel/rcu/srcutree.c:730
 srcu_advance_state kernel/rcu/srcutree.c:1167 [inline]
 process_srcu+0x642/0x1400 kernel/rcu/srcutree.c:1261
 process_one_work+0xd0c/0x1ce0 kernel/workqueue.c:2153
 worker_thread+0x143/0x14a0 kernel/workqueue.c:2296
 kthread+0x357/0x430 kernel/kthread.c:246
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352