Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b

CPU: 1 PID: 1 Comm: init Not tainted 4.15.0-rc3+ #225
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x194/0x257 lib/dump_stack.c:53
 panic+0x1e4/0x41c kernel/panic.c:183
 find_child_reaper kernel/exit.c:578 [inline]
 forget_original_parent+0x1337/0x1b90 kernel/exit.c:670
 exit_notify+0x11f/0xb10 kernel/exit.c:706
 do_exit+0x9f2/0x1ad0 kernel/exit.c:885
 do_group_exit+0x149/0x400 kernel/exit.c:968
 get_signal+0x73f/0x16c0 kernel/signal.c:2335
 do_signal+0x94/0x1ee0 arch/x86/kernel/signal.c:809
 exit_to_usermode_loop+0x214/0x310 arch/x86/entry/common.c:158
 prepare_exit_to_usermode+0x2e1/0x340 arch/x86/entry/common.c:195
 retint_user+0x8/0x18
RIP: 0033:0x7fa143c620cb
RSP: 002b:00007ffcf8010a40 EFLAGS: 00010202
RAX: 0000000000000000 RBX: 00007ffcf8010a40 RCX: 00007fa143c61f46
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 00007ffcf8010a80 R08: 0000000000000000 R09: 0000000000000001
R10: 00007fa1445b6a70 R11: 0000000000000246 R12: 0000000000002bda
R13: 00000000000000ca R14: 0000000000000081 R15: 0000000000000000
Dumping ftrace buffer:
   (ftrace buffer empty)
Kernel Offset: disabled
Rebooting in 86400 seconds..