------------[ cut here ]------------
kobject_add_internal failed for 7:199-fuseblk with -EEXIST, don't try to register things with the same name in the same directory.
WARNING: CPU: 0 PID: 4485 at lib/kobject.c:238 kobject_add_internal+0x8e0/0xba0 lib/kobject.c:236
Kernel panic - not syncing: panic_on_warn set ...

CPU: 0 PID: 4485 Comm: syzkaller020590 Not tainted 4.16.0+ #2
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1b9/0x294 lib/dump_stack.c:113
 panic+0x22f/0x4de kernel/panic.c:184
 __warn.cold.8+0x163/0x1b3 kernel/panic.c:536
 report_bug+0x252/0x2d0 lib/bug.c:186
 fixup_bug arch/x86/kernel/traps.c:178 [inline]
 do_error_trap+0x1de/0x490 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:kobject_add_internal+0x8e0/0xba0 lib/kobject.c:236
RSP: 0018:ffff8801acfa7250 EFLAGS: 00010286
RAX: 0000000000000082 RBX: ffff8801ade44dd0 RCX: ffffffff815f58cd
RDX: 0000000000000000 RSI: ffffffff815fa581 RDI: ffff8801acfa6db0
RBP: ffff8801acfa7348 R08: ffff8801ace7a740 R09: 0000000000000006
R10: ffff8801ace7a740 R11: 0000000000000000 R12: 00000000ffffffef
R13: ffff8801d3773480 R14: 1ffff100359f4e54 R15: ffff8801d9fc8f00
 kobject_add_varg lib/kobject.c:364 [inline]
 kobject_add+0x13a/0x190 lib/kobject.c:408
 device_add+0x3a5/0x16d0 drivers/base/core.c:1796
 device_create_groups_vargs+0x1ff/0x270 drivers/base/core.c:2439
 device_create_vargs+0x46/0x60 drivers/base/core.c:2479
 bdi_register_va.part.10+0xbb/0x970 mm/backing-dev.c:868
 bdi_register_va+0x68/0x80 mm/backing-dev.c:884
 super_setup_bdi_name+0x123/0x220 fs/super.c:1320
 fuse_bdi_init fs/fuse/inode.c:987 [inline]
 fuse_fill_super+0xe6e/0x1e20 fs/fuse/inode.c:1110
 mount_bdev+0x30c/0x3e0 fs/super.c:1165
 fuse_mount_blk+0x34/0x40 fs/fuse/inode.c:1222
 mount_fs+0xae/0x328 fs/super.c:1268
 vfs_kern_mount.part.34+0xd4/0x4d0 fs/namespace.c:1037
 vfs_kern_mount fs/namespace.c:1027 [inline]
 do_new_mount fs/namespace.c:2517 [inline]
 do_mount+0x564/0x3070 fs/namespace.c:2847
 ksys_mount+0x12d/0x140 fs/namespace.c:3063
 SYSC_mount fs/namespace.c:3077 [inline]
 SyS_mount+0x35/0x50 fs/namespace.c:3074
 do_syscall_64+0x29e/0x9d0 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x440789
RSP: 002b:00007ffed10b2b78 EFLAGS: 00000206 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000440789
RDX: 00000000004a278e RSI: 0000000020000080 RDI: 00000000200000c0
RBP: 0030656c69662f2e R08: 00007ffed10b2b90 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000401b20
R13: 0000000000401bb0 R14: 0000000000000000 R15: 0000000000000000
Dumping ftrace buffer:
   (ftrace buffer empty)
Kernel Offset: disabled
Rebooting in 86400 seconds..