RBP: 00007fd44a08da90 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000212 R12: 00000000004b767a R13: 00007fd44a08dbc8 R14: 00000000004b767a R15: 0000000000000000 ------------[ cut here ]------------ sysfs group 'loop' not found for kobject 'loop0' WARNING: CPU: 0 PID: 6231 at fs/sysfs/group.c:237 sysfs_remove_group+0x15b/0x1b0 fs/sysfs/group.c:235 Kernel panic - not syncing: panic_on_warn set ... CPU: 0 PID: 6231 Comm: syz-executor2 Not tainted 4.15.0-rc6-mm1+ #52 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 __warn+0x1dc/0x200 kernel/panic.c:547 report_bug+0x211/0x2d0 lib/bug.c:184 fixup_bug.part.11+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+0x22/0x40 arch/x86/entry/entry_64.S:1079 RIP: 0010:sysfs_remove_group+0x15b/0x1b0 fs/sysfs/group.c:235 RSP: 0018:ffff8801bcbc79a8 EFLAGS: 00010282 RAX: dffffc0000000008 RBX: ffffffff86d07260 RCX: ffffffff815a13ee RDX: 0000000000000502 RSI: ffffc90002077000 RDI: 0000000000000212 RBP: ffff8801bcbc79d0 R08: 1ffff10037978ec8 R09: 0000000000000000 R10: ffffffff87f47e60 R11: 0000000000000000 R12: 0000000000000000 R13: ffff8801d9108e60 R14: ffffffff86098480 R15: ffff8801d9b90368 loop_sysfs_exit drivers/block/loop.c:798 [inline] loop_clr_fd+0x4f2/0xb50 drivers/block/loop.c:1051 lo_ioctl+0x1307/0x1b70 drivers/block/loop.c:1365 __blkdev_driver_ioctl block/ioctl.c:303 [inline] blkdev_ioctl+0x1759/0x1e00 block/ioctl.c:601 block_ioctl+0xde/0x120 fs/block_dev.c:1859 vfs_ioctl fs/ioctl.c:46 [inline] do_vfs_ioctl+0x1b1/0x1520 fs/ioctl.c:686 SYSC_ioctl fs/ioctl.c:701 [inline] SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692 entry_SYSCALL_64_fastpath+0x23/0x9a RIP: 0033:0x452ac9 RSP: 002b:00007fd44a08dc58 EFLAGS: 00000212 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fd44a08e700 RCX: 0000000000452ac9 RDX: 0000000000000000 RSI: 0000000000004c01 RDI: 0000000000000013 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000212 R12: 0000000000000000 R13: 0000000000a2f7ef R14: 00007fd44a08e9c0 R15: 0000000000000000 Dumping ftrace buffer: (ftrace buffer empty) Kernel Offset: disabled Rebooting in 86400 seconds..