Comment 3 for bug 1252063

Hitting this issue on Fresh install of Ubuntu Server 14.04 LTS x86_64.

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root@gr3:~# mkfs.nilfs2 -f /dev/sdb1
mkfs.nilfs2 (nilfs-utils 2.1.5)
Start writing file system initial data to the device
       Blocksize:4096 Device:/dev/sdb1 Device Size:146162057216
File system initialization succeeded !!
root@gr3:~# mount /dev/sd
sda sda1 sda2 sda5 sdb sdb1 sdc sdc1 sdd sdd1
root@gr3:~# mount /dev/sd
sda sda1 sda2 sda5 sdb sdb1 sdc sdc1 sdd sdd1
root@gr3:~# mount /dev/sdb1 /test/root/
root@gr3:~# umount /test/root
umount.nilfs2: /dev/sdb1: device is busy
umount.nilfs2: /dev/sdb1: device is busy
root@gr3:~# ps -A | grep nilfs
 1313 ? 00:00:00 nilfs_cleanerd
root@gr3:~# kill -9 1313
root@gr3:~# umount /test/root
root@gr3:~# lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 14.04 LTS
Release: 14.04
Codename: trusty
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