EXT4-fs (sda1): re-mounted. Opts: 
EXT4-fs (sda1): re-mounted. Opts: 
EXT4-fs (sda1): re-mounted. Opts: 
EXT4-fs (sda1): re-mounted. Opts: 
EXT4-fs (sda1): re-mounted. Opts: 
INFO: rcu_sched self-detected stall on CPU
	0-...!: (124998 ticks this GP) idle=59a/1/4611686018427387906 softirq=99006/99006 fqs=0 
	 (t=125000 jiffies g=50394 c=50393 q=32)
rcu_sched kthread starved for 125000 jiffies! g50394 c50393 f0x0 RCU_GP_WAIT_FQS(3) ->state=0x0 ->cpu=1
RCU grace-period kthread stack dump:
rcu_sched       R  running task    23896     9      2 0x80000000
Call Trace:
 context_switch kernel/sched/core.c:2859 [inline]
 __schedule+0x801/0x1e30 kernel/sched/core.c:3501
 schedule+0xef/0x430 kernel/sched/core.c:3545
 schedule_timeout+0x138/0x240 kernel/time/timer.c:1801
 rcu_gp_kthread+0x6b5/0x1940 kernel/rcu/tree.c:2231
 kthread+0x345/0x410 kernel/kthread.c:240
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:412
NMI backtrace for cpu 0
CPU: 0 PID: 4536 Comm: syz-executor904 Not tainted 4.17.0-rc6+ #70
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1b9/0x294 lib/dump_stack.c:113
 nmi_cpu_backtrace.cold.4+0x19/0xce lib/nmi_backtrace.c:103
 nmi_trigger_cpumask_backtrace+0x151/0x192 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:156 [inline]
 rcu_dump_cpu_stacks+0x175/0x1c2 kernel/rcu/tree.c:1376
 print_cpu_stall kernel/rcu/tree.c:1525 [inline]
 check_cpu_stall.isra.61.cold.80+0x36c/0x59a kernel/rcu/tree.c:1593
 __rcu_pending kernel/rcu/tree.c:3356 [inline]
 rcu_pending kernel/rcu/tree.c:3401 [inline]
 rcu_check_callbacks+0x21b/0xad0 kernel/rcu/tree.c:2763
 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+0x3e3/0x10a0 kernel/time/hrtimer.c:1460
 hrtimer_interrupt+0x2f3/0x750 kernel/time/hrtimer.c:1518
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1025 [inline]
 smp_apic_timer_interrupt+0x15d/0x710 arch/x86/kernel/apic/apic.c:1050
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:863
 </IRQ>
RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:783 [inline]
RIP: 0010:seqcount_lockdep_reader_access include/linux/seqlock.h:83 [inline]
RIP: 0010:read_seqcount_begin include/linux/seqlock.h:164 [inline]
RIP: 0010:read_seqbegin include/linux/seqlock.h:433 [inline]
RIP: 0010:read_seqbegin_or_lock include/linux/seqlock.h:529 [inline]
RIP: 0010:d_walk+0x840/0xc80 fs/dcache.c:1248
RSP: 0018:ffff8801ae0ff9f8 EFLAGS: 00000293 ORIG_RAX: ffffffffffffff13
RAX: ffff8801acfb6340 RBX: 0000000000000293 RCX: 1ffff100359f6d7d
RDX: 0000000000000000 RSI: ffffffff81c6691b RDI: 0000000000000293
RBP: ffff8801ae0ffb78 R08: ffff8801acfb6b78 R09: 0000000000000006
R10: ffff8801acfb6340 R11: 0000000000000000 R12: 0000000000000200
R13: dffffc0000000000 R14: 1ffff10035c1ff82 R15: ffff8801ae0ffb50
 shrink_dcache_parent+0x179/0x230 fs/dcache.c:1486
 vfs_rmdir+0x202/0x470 fs/namei.c:3850
 do_rmdir+0x523/0x610 fs/namei.c:3911
 __do_sys_rmdir fs/namei.c:3929 [inline]
 __se_sys_rmdir fs/namei.c:3927 [inline]
 __x64_sys_rmdir+0x36/0x40 fs/namei.c:3927
 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x441837
RSP: 002b:00007ffc2d96b798 EFLAGS: 00000207 ORIG_RAX: 0000000000000054
RAX: ffffffffffffffda RBX: 0000000000000065 RCX: 0000000000441837
RDX: 0000000000000000 RSI: 00000000006cd858 RDI: 00007ffc2d96c880
RBP: 00007ffc2d96c880 R08: 0000000000000000 R09: 0000000000000001
R10: 0000000000000006 R11: 0000000000000207 R12: 00000000016928a0
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000