Comment # 24 on bug 1080485 from Ronnie Bailey

  I had opened a thread in the openSUSE Tumbleweed forum regarding this
problem. A user has found a workaround that may at least give a hint as to what
is going on. 
 It was posted that: "Adding "plymouth.enable=0" to the kernel parameters makes
the "device-mapper: remove ioctl on XXXXX failed: Device or resource busy"
messages disappear."
 I have no idea if Plymouth is the problem or just a direction to look. I can
verify that adding the above kernel parameter has stopped the error in my
Tumbleweed machine. My original thread may be found at:

https://forums.opensuse.org/showthread.php/530530-device-mapper-remove-ioctl-on-system-root-failed