What version of Ubuntu was he installing? GRUB is supposed to work fine on XFS these days, and it certainly isn't restricted to just ext[234]. The reason you didn't find any documentation about prerequisite filesystems is that there aren't supposed to be any. :-)
** Package changed: ubiquity (Ubuntu) => grub-installer (Ubuntu) ** Changed in: grub-installer (Ubuntu) Status: New => Incomplete -- Installing Ubuntu with manual partition allows grub-incompatible filesystems on /boot https://bugs.launchpad.net/bugs/438246 You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs