Buffer I/O error on dev loop0, logical block 7, async page read
------------[ cut here ]------------
WARNING: CPU: 1 PID: 5 at net/kcm/kcmsock.c:2014 kcm_exit_net+0x317/0x360 net/kcm/kcmsock.c:2014
Kernel panic - not syncing: panic_on_warn set ...

CPU: 1 PID: 5 Comm: kworker/u4:0 Not tainted 4.14.0-rc2+ #106
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: netns cleanup_net
Call Trace:
 __dump_stack lib/dump_stack.c:16 [inline]
 dump_stack+0x194/0x257 lib/dump_stack.c:52
 panic+0x1e4/0x417 kernel/panic.c:181
 __warn+0x1c4/0x1d9 kernel/panic.c:542
 report_bug+0x211/0x2d0 lib/bug.c:183
 fixup_bug+0x40/0x90 arch/x86/kernel/traps.c:178
 do_trap_no_signal arch/x86/kernel/traps.c:212 [inline]
 do_trap+0x260/0x390 arch/x86/kernel/traps.c:261
 do_error_trap+0x120/0x390 arch/x86/kernel/traps.c:298
 do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:311
 invalid_op+0x18/0x20 arch/x86/entry/entry_64.S:905
RIP: 0010:kcm_exit_net+0x317/0x360 net/kcm/kcmsock.c:2014
RSP: 0018:ffff8801d9f2f198 EFLAGS: 00010297
RAX: ffff8801d9f20140 RBX: 1ffff1003b3e5e33 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffffed003b3e5e28
RBP: ffff8801d9f2f260 R08: 0000000000000000 R09: 1ffff1003b3e5e0c
R10: ffff8801d9f20140 R11: 0000000000000003 R12: 1ffff1003b3e5e37
R13: ffff8801d9f2f238 R14: ffff8801c1a5e620 R15: ffff8801c496a380
 ops_exit_list.isra.6+0xae/0x150 net/core/net_namespace.c:142
 cleanup_net+0x5c7/0xb60 net/core/net_namespace.c:483
 process_one_work+0xbfa/0x1bd0 kernel/workqueue.c:2119
 worker_thread+0x223/0x1860 kernel/workqueue.c:2253
 kthread+0x39c/0x470 kernel/kthread.c:231
 ret_from_fork+0x2a/0x40 arch/x86/entry/entry_64.S:431
Dumping ftrace buffer:
   (ftrace buffer empty)
Kernel Offset: disabled
Rebooting in 86400 seconds..