Comment 9 for bug 439784

Incidentally, there is a very good reason why loadenv doesn't create the
environment block itself - GRUB's filesystem modules don't have write
support, and adding that would expose us to a whole range of exciting
new possible bugs. For this reason, we create the file when we're in a
real operating system, and all GRUB has to do is write into a
pre-allocated block on the disk, which is pretty simple and safe.

Is your problem perhaps that loadenv is finding a zero-sized environment
block and failing before we boot into Ubuntu at all? If that's what's
happening, then we could make it treat a zero-sized block like an absent
one, or something like that.