Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x1b2/0x281 lib/dump_stack.c:58
 fail_dump lib/fault-inject.c:51 [inline]
 should_fail.cold+0x10a/0x149 lib/fault-inject.c:149
------------[ cut here ]------------
 should_failslab+0xd6/0x130 mm/failslab.c:32
WARNING: CPU: 1 PID: 17033 at fs/super.c:1163 kill_block_super+0xbe/0xe0 fs/super.c:1163
 slab_pre_alloc_hook mm/slab.h:421 [inline]
 slab_alloc mm/slab.c:3376 [inline]
 kmem_cache_alloc+0x28e/0x3c0 mm/slab.c:3550
Kernel panic - not syncing: panic_on_warn set ...

 kmem_cache_zalloc include/linux/slab.h:651 [inline]
 __kernfs_new_node+0x6f/0x470 fs/kernfs/dir.c:632
 kernfs_new_node fs/kernfs/dir.c:677 [inline]
 kernfs_create_dir_ns+0x8c/0x200 fs/kernfs/dir.c:998
 kernfs_create_dir include/linux/kernfs.h:502 [inline]
 internal_create_group+0xe9/0x710 fs/sysfs/group.c:124
 loop_sysfs_init drivers/block/loop.c:821 [inline]
 loop_set_fd drivers/block/loop.c:946 [inline]
 lo_ioctl+0x1137/0x1cd0 drivers/block/loop.c:1417
 __blkdev_driver_ioctl block/ioctl.c:297 [inline]
 blkdev_ioctl+0x540/0x1830 block/ioctl.c:594
 block_ioctl+0xd9/0x120 fs/block_dev.c:1893
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:500 [inline]
 do_vfs_ioctl+0x75a/0xff0 fs/ioctl.c:684
 SYSC_ioctl fs/ioctl.c:701 [inline]
 SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x7f4e3b55dea7
RSP: 002b:00007f4e39ed2f28 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f4e3b5a7a20 RCX: 00007f4e3b55dea7
RDX: 0000000000000004 RSI: 0000000000004c00 RDI: 0000000000000005
RBP: 0000000000000005 R08: 0000000000000000 R09: 00007f4e39ed31d0
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000004
R13: 0000000000000004 R14: 0000000020001170 R15: 0000000000000002
CPU: 1 PID: 17033 Comm: syz-executor.5 Not tainted 4.14.277-syzkaller #0
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+0x1b2/0x281 lib/dump_stack.c:58
 panic+0x1f9/0x42d kernel/panic.c:183
 __warn.cold+0x20/0x44 kernel/panic.c:547
 report_bug+0x208/0x250 lib/bug.c:183
 fixup_bug arch/x86/kernel/traps.c:177 [inline]
 fixup_bug arch/x86/kernel/traps.c:172 [inline]
 do_error_trap+0x195/0x2d0 arch/x86/kernel/traps.c:295
 invalid_op+0x1b/0x40 arch/x86/entry/entry_64.S:964
RIP: 0010:kill_block_super+0xbe/0xe0 fs/super.c:1163
RSP: 0018:ffff8880a4b9fbc8 EFLAGS: 00010246
RAX: 0000000000040000 RBX: 0000000000000000 RCX: ffffc900075bf000
RDX: 0000000000040000 RSI: ffffffff818759be RDI: ffff8880b1fa4630
RBP: ffff8880b10c46c0 R08: ffffffff8b9e1fe0 R09: 0000000000000001
R10: 0000000000000000 R11: ffff888094e1e640 R12: ffff8880b1fa4180
R13: ffffffff891e9e70 R14: ffffffff88f45500 R15: dffffc0000000000
 deactivate_locked_super+0x6c/0xd0 fs/super.c:319
 sget_userns+0x9c4/0xc10 fs/super.c:537
 sget+0xd1/0x110 fs/super.c:572
 mount_bdev+0xcd/0x360 fs/super.c:1107
 mount_fs+0x92/0x2a0 fs/super.c:1237
 vfs_kern_mount.part.0+0x5b/0x470 fs/namespace.c:1046
 vfs_kern_mount fs/namespace.c:1036 [inline]
 do_new_mount fs/namespace.c:2572 [inline]
 do_mount+0xe65/0x2a10 fs/namespace.c:2902
 SYSC_mount fs/namespace.c:3118 [inline]
 SyS_mount+0xa8/0x120 fs/namespace.c:3095
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x7fc67c3f60e9
RSP: 002b:00007fc67ad6b168 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007fc67c508f60 RCX: 00007fc67c3f60e9
RDX: 00000000200003c0 RSI: 0000000020000380 RDI: 0000000020000340
RBP: 00007fc67ad6b1d0 R08: 0000000020000540 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000002
R13: 00007ffecb48a90f R14: 00007fc67ad6b300 R15: 0000000000022000
Kernel Offset: disabled
Rebooting in 86400 seconds..