rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	1-...!: (1 ticks this GP) idle=aae/1/0x4000000000000002 softirq=86237/86237 fqs=0 
	(t=11135 jiffies g=130377 q=443)
rcu: rcu_preempt kthread starved for 11135 jiffies! g130377 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=1
rcu: RCU grace-period kthread stack dump:
rcu_preempt     I28952    10      2 0x80004000
Call Trace:
 context_switch kernel/sched/core.c:3384 [inline]
 __schedule+0x74b/0xb80 kernel/sched/core.c:4069
 schedule+0x131/0x1e0 kernel/sched/core.c:4136
 schedule_timeout+0x14f/0x240 kernel/time/timer.c:1895
 rcu_gp_fqs_loop kernel/rcu/tree.c:1639 [inline]
 rcu_gp_kthread+0xed8/0x1770 kernel/rcu/tree.c:1799
 kthread+0x332/0x350 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
NMI backtrace for cpu 1
CPU: 1 PID: 32673 Comm: kworker/1:8 Not tainted 5.4.0-rc5 #0
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+0x1d8/0x2f8 lib/dump_stack.c:113
 nmi_cpu_backtrace+0xaf/0x1a0 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x174/0x290 lib/nmi_backtrace.c:62
 arch_trigger_cpumask_backtrace+0x10/0x20 arch/x86/kernel/apic/hw_nmi.c:38
 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline]
 rcu_dump_cpu_stacks+0x15a/0x220 kernel/rcu/tree_stall.h:254
 print_cpu_stall kernel/rcu/tree_stall.h:455 [inline]
 check_cpu_stall kernel/rcu/tree_stall.h:529 [inline]
 rcu_pending kernel/rcu/tree.c:2795 [inline]
 rcu_sched_clock_irq+0xe22/0x1ae0 kernel/rcu/tree.c:2244
 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:1299
 __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:830
 </IRQ>
RIP: 0010:preempt_count_add+0x12/0x160 kernel/sched/core.c:3786
Code: ff ff 4c 89 e7 e8 9e 85 5c 00 e9 2e ff ff ff 66 0f 1f 84 00 00 00 00 00 55 48 89 e5 41 57 41 56 53 89 fb 65 01 3d 6a 00 b2 7e <48> c7 c0 60 dd 9e 89 48 c1 e8 03 49 bf 00 00 00 00 00 fc ff df 42
RSP: 0018:ffff88807f787b20 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13
RAX: 0000000080000000 RBX: 0000000000000001 RCX: 0000000000000001
RDX: 0000000000000254 RSI: 0000000000000001 RDI: 0000000000000001
RBP: ffff88807f787b38 R08: ffffffff83484c5a R09: fffffbfff111fd50
R10: fffffbfff111fd50 R11: 0000000000000000 R12: 00000254157c00e1
R13: 0000000000000000 R14: 0000000000002ced R15: 0000000000000001
 delay_tsc+0xa0/0xf0 arch/x86/lib/delay.c:68
 __delay arch/x86/lib/delay.c:161 [inline]
 __const_udelay+0x5e/0x70 arch/x86/lib/delay.c:175
 try_check_zero+0x6e/0x380 kernel/rcu/srcutree.c:705
 srcu_advance_state kernel/rcu/srcutree.c:1142 [inline]
 process_srcu+0x1b7/0xd20 kernel/rcu/srcutree.c:1237
 process_one_work+0x7ef/0x10e0 kernel/workqueue.c:2269
 worker_thread+0xc01/0x1630 kernel/workqueue.c:2415
 kthread+0x332/0x350 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
protocol 88fb is buggy, dev hsr_slave_0
protocol 88fb is buggy, dev hsr_slave_1