Openstack Cinder Leaves Lots of Old Lock Files

Issue

A lot of lock files in /var/lib/cinder can be seen on the controllers, some of these are from no longer existing volumes. The formatting is something like cinder-{VOLUME_UUID}-{(delete_volume|delete_snapshot|detach_volume)}.
Deleting these files results in not able to migrate instance with attached volumes, and/or not being able to attach volumes.