RBP: 0000000000000000 R08: 000000000000000a R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dbc54
R13: 0000000000000016 R14: 00000000006dbc50 R15: 0000000000000010
------------[ cut here ]------------
sysfs group 'loop' not found for kobject 'loop0'
WARNING: CPU: 0 PID: 4459 at fs/sysfs/group.c:235 sysfs_remove_group+0x15b/0x1b0 fs/sysfs/group.c:233
Kernel panic - not syncing: panic_on_warn set ...

CPU: 0 PID: 4459 Comm: syzkaller999479 Not tainted 4.16.0+ #14
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+0x1a7/0x27d lib/dump_stack.c:53
 panic+0x1f8/0x42c kernel/panic.c:183
 __warn+0x1dc/0x200 kernel/panic.c:547
 report_bug+0x1f4/0x2b0 lib/bug.c:186
 fixup_bug.part.10+0x37/0x80 arch/x86/kernel/traps.c:178
 fixup_bug arch/x86/kernel/traps.c:247 [inline]
 do_error_trap+0x2d7/0x3e0 arch/x86/kernel/traps.c:296
 do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:315
 invalid_op+0x1b/0x40 arch/x86/entry/entry_64.S:991
RIP: 0010:sysfs_remove_group+0x15b/0x1b0 fs/sysfs/group.c:233
RSP: 0018:ffff8801b0c4f930 EFLAGS: 00010282
RAX: dffffc0000000008 RBX: ffffffff88a60440 RCX: ffffffff815b5d2e
RDX: 0000000000000000 RSI: 1ffff10036189ed6 RDI: 1ffff10036189eab
RBP: ffff8801b0c4f958 R08: 1ffff10036189e6d R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000000
R13: ffff8801d333c1a0 R14: fffffff