Ubuntu Server as a host OS for LE build system, not for DVD playback.
Maybe I wasn't clear in my original post... The resulting RPi2 images don't play any DVDs (including VIDEO_TS folders and ISOs) unless I disable LTO in Kodi's package.mk. I reported about the issue here a while ago but milhouse have no idea what's causing this.
This issue occur even if I don't make any changes (a clean build from current LE master).