[[!comment format=mdwn username="joey" subject="""comment 2""" date="2017-12-20T21:36:36Z" content=""" AFAICS, DiskImage.imageFinalized creates any mount points that were not rsynced over from the chroot. But, I guess that partitionsPopulated is expecting the mount point to exist in order to rsync its content over, and if nothing created /boot/efi that would explain the rsync error. I've added a check to prevent that problem. As for the unmount problem, it's a problem with the order it traverses the mount points for unmounting. That is using "unmountBelow" with the directory where the disk image partitions are loop mounted. If that unmounts `boot` first, it will implicitly unmount `boot/efi` (due to --lazy) and then will fail when it tries to explicitly unmount it. Added sorting that should fix that. Let me know how that goes, I've not tested it with your config. """]]