FAT-fs (loop6): Unrecognized mount option "./file0/file0/file0" or missing value
INFO: rcu_sched self-detected stall on CPU
	0-....: (124999 ticks this GP) idle=8ca/1/4611686018427387906 softirq=81711/81711 fqs=31228 
	 (t=125000 jiffies g=44076 c=44075 q=286)
NMI backtrace for cpu 0
CPU: 0 PID: 21751 Comm: syz-executor7 Not tainted 4.16.0+ #15
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x1a7/0x27d lib/dump_stack.c:53
 nmi_cpu_backtrace+0x1e0/0x220 lib/nmi_backtrace.c:103
 nmi_trigger_cpumask_backtrace+0x123/0x180 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+0x186/0x1d3 kernel/rcu/tree.c:1376
 print_cpu_stall kernel/rcu/tree.c:1525 [inline]
 check_cpu_stall.isra.63+0xbb8/0x15b0 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/0xae0 kernel/rcu/tree.c:2763
 update_process_times+0x30/0x60 kernel/time/timer.c:1636
 tick_sched_handle+0x85/0x160 kernel/time/tick-sched.c:162
 tick_sched_timer+0x42/0x120 kernel/time/tick-sched.c:1170
 __run_hrtimer kernel/time/hrtimer.c:1349 [inline]
 __hrtimer_run_queues+0x39c/0xec0 kernel/time/hrtimer.c:1411
 hrtimer_interrupt+0x2a5/0x6f0 kernel/time/hrtimer.c:1469
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1025 [inline]
 smp_apic_timer_interrupt+0x14a/0x700 arch/x86/kernel/apic/apic.c:1050
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:862
 </IRQ>
RIP: 0010:get_current arch/x86/include/asm/current.h:15 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0xa/0x50 kernel/kcov.c:100
RSP: 0018:ffff8801908377b8 EFLAGS: 00000296 ORIG_RAX: ffffffffffffff12
RAX: ffff8801ca67a640 RBX: ffffc900029ec000 RCX: ffffffff8355b242
RDX: 0000000000040000 RSI: ffffc90003aae000 RDI: ffffc900029ede2b
RBP: ffff880190837830 R08: 1ffff10032106e9f R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000526d4ebcc
R13: dffffc0000000000 R14: 0000000526d4ebcc R15: 00000000000011cf
 flush_echoes drivers/tty/n_tty.c:799 [inline]
 __receive_buf drivers/tty/n_tty.c:1615 [inline]
 n_tty_receive_buf_common+0x1380/0x2520 drivers/tty/n_tty.c:1709
 n_tty_receive_buf+0x30/0x40 drivers/tty/n_tty.c:1738
 tiocsti drivers/tty/tty_io.c:2171 [inline]
 tty_ioctl+0x9c5/0x1620 drivers/tty/tty_io.c:2557
 vfs_ioctl fs/ioctl.c:46 [inline]
 do_vfs_ioctl+0x1b1/0x1520 fs/ioctl.c:686
 ksys_ioctl+0x94/0xb0 fs/ioctl.c:701
 SYSC_ioctl fs/ioctl.c:708 [inline]
 SyS_ioctl+0x24/0x30 fs/ioctl.c:706
 do_syscall_64+0x281/0x940 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x4552d9
RSP: 002b:00007fdda0897c68 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fdda08986d4 RCX: 00000000004552d9
RDX: 00000000200000c0 RSI: 0000000000005412 RDI: 0000000000000019
RBP: 000000000072c010 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000000002f9 R14: 00000000006f77f8 R15: 0000000000000002