TITLE: INFO: rcu detected stall in rtc_timer_do_work

[  249.033000] INFO: rcu_sched self-detected stall on CPU
[  249.038403] 	1-....: (10499 ticks this GP) idle=35e/140000000000001/0 softirq=17797/17797 fqs=5227 
[  249.047693] 	 (t=10500 jiffies g=2803 c=2802 q=3452)
[  249.052792] NMI backtrace for cpu 1
[  249.056404] CPU: 1 PID: 17 Comm: kworker/1:0 Not tainted 4.15.0 #10
[  249.062875] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
[  249.072229] Workqueue: events rtc_timer_do_work
[  249.076884] Call Trace:
[  249.079451]  <IRQ>
[  249.081604]  [<ffffffff8415f2a2>] dump_stack+0x14d/0x20b
[  249.087048]  [<ffffffff8134e501>] ? x86_vector_activate.cold+0xb8/0xb8
[  249.093726]  [<ffffffff8416b827>] nmi_cpu_backtrace.cold+0x19/0x98
[  249.100055]  [<ffffffff8134e580>] ? lapic_can_unplug_cpu.cold+0x38/0x38
[  249.106804]  [<ffffffff8416b7fa>] nmi_trigger_cpumask_backtrace+0x16a/0x17e
[  249.113916]  [<ffffffff8134e694>] arch_trigger_cpumask_backtrace+0x14/0x20
[  249.120980]  [<ffffffff815a3ade>] rcu_dump_cpu_stacks+0x189/0x1d5
[  249.127214]  [<ffffffff815a47e3>] rcu_check_callbacks.cold+0x51c/0xc29
[  249.133888]  [<ffffffff81477b6c>] ? irqtime_account_process_tick.isra.0+0x2cc/0x470
[  249.141773]  [<ffffffff815bf462>] update_process_times+0x32/0x80
[  249.147916]  [<ffffffff815f1fe0>] tick_sched_handle+0xa0/0x180
[  249.153888]  [<ffffffff815f25d4>] tick_sched_timer+0x44/0x130
[  249.159768]  [<ffffffff815c30f7>] __hrtimer_run_queues+0x307/0xd90
[  249.166111]  [<ffffffff815f2590>] ? tick_sched_do_timer+0x110/0x110
[  249.172529]  [<ffffffff815c2df0>] ? hrtimer_start_range_ns+0xc20/0xc20
[  249.179213]  [<ffffffff815c4bea>] hrtimer_interrupt+0x2ea/0x730
[  249.185287]  [<ffffffff842050f4>] smp_apic_timer_interrupt+0x144/0x5e0
[  249.191970]  [<ffffffff84201cbe>] apic_timer_interrupt+0x8e/0xa0
[  249.198108]  </IRQ>
[  249.200451] RIP: 0010:rtc_timer_do_work+0x21a/0x650
[  249.205465] RSP: 0018:ffff8801d930bb70 EFLAGS: 00000a02 ORIG_RAX: ffffffffffffff12
[  249.213175] RAX: ffffffff83456f90 RBX: dffffc0000000000 RCX: 1ffff1003a100b1c
[  249.220455] RDX: 1ffff1003a100b26 RSI: ffffffff834572d7 RDI: ffff8801d0805930
[  249.228144] RBP: ffff8801d930bd00 R08: ffff8801d92fe100 R09: 0000000000000000
[  249.235407] R10: 0000000000000000 R11: 0000000000000000 R12: ffff8801d0805938
[  249.242751] R13: 2b64ae95de020000 R14: ffff8801d0805950 R15: ffff8801d0805960
[  249.250020]  [<ffffffff83456f90>] ? rtc_aie_update_irq+0x30/0x30
[  249.256172]  [<ffffffff834572d7>] ? rtc_timer_do_work+0x207/0x650
[  249.262392]  [<ffffffff84200a6b>] ? retint_kernel+0x10/0x10
[  249.268094]  [<ffffffff83456f90>] ? rtc_aie_update_irq+0x30/0x30
[  249.274227]  [<ffffffff834570d0>] ? rtc_pie_update_irq+0x110/0x110
[  249.280536]  [<ffffffff8152468a>] ? __lock_is_held+0xba/0x140
[  249.286497]  [<ffffffff81411f96>] process_one_work+0x886/0x1650
[  249.292543]  [<ffffffff834570d0>] ? rtc_pie_update_irq+0x110/0x110
[  249.298850]  [<ffffffff81411f96>] ? process_one_work+0x886/0x1650
[  249.305280]  [<ffffffff8100094b>] ? __schedule+0x59b/0x1d40
[  249.310981]  [<ffffffff81411710>] ? pwq_dec_nr_in_flight+0x310/0x310
[  249.317483]  [<ffffffff81530b4c>] ? lock_acquire+0x10c/0x330
[  249.323298]  [<ffffffff81014998>] ? _raw_spin_unlock_irq+0x28/0x40
[  249.329617]  [<ffffffff814133b3>] worker_thread+0x653/0x1150
[  249.335431]  [<ffffffff8142aae8>] kthread+0x348/0x420
[  249.340610]  [<ffffffff81412d60>] ? process_one_work+0x1650/0x1650
[  249.346921]  [<ffffffff8142a7a0>] ? kthread_create_worker_on_cpu+0xf0/0xf0
[  249.353923]  [<ffffffff84200261>] ret_from_fork+0x61/0x70
[  255.918447] INFO: rcu_sched detected expedited stalls on CPUs/tasks: { 1-... } 10879 jiffies s: 529 root: 0x2/.
[  255.929073] blocking rcu_node structures:
[  255.933240] Task dump for CPU 1:
[  255.936606] kworker/1:0     R  running task on cpu   1  11096    17      2 0x80000008 144014221083
[  255.945801] Workqueue: events rtc_timer_do_work
[  255.950691] Call Trace:
[  255.953500]  [<ffffffff81411f96>] ? process_one_work+0x886/0x1650
[  255.959955]  [<ffffffff834570d0>] ? rtc_pie_update_irq+0x110/0x110
[  255.966286]  [<ffffffff81411f96>] ? process_one_work+0x886/0x1650
[  255.972682]  [<ffffffff8100094b>] ? __schedule+0x59b/0x1d40
[  255.978449]  [<ffffffff81411710>] ? pwq_dec_nr_in_flight+0x310/0x310
[  255.984954]  [<ffffffff81530b4c>] ? lock_acquire+0x10c/0x330
[  255.990805]  [<ffffffff81014998>] ? _raw_spin_unlock_irq+0x28/0x40
[  255.997150]  [<ffffffff814133b3>] ? worker_thread+0x653/0x1150
[  256.003229]  [<ffffffff8142aae8>] ? kthread+0x348/0x420
[  256.008664]  [<ffffffff81412d60>] ? process_one_work+0x1650/0x1650
[  256.015102]  [<ffffffff8142a7a0>] ? kthread_create_worker_on_cpu+0xf0/0xf0
[  256.022185]  [<ffffffff84200261>] ? ret_from_fork+0x61/0x70