Comment 7 for bug 729467

I can reproduce this issue, but for me this does NOT return successfully:
sudo -E blkid -o udev -p -c /dev/null /dev/sdb2

it returns error code 2, which I guess means that the UUID can't be found.

I'm wondering: Matt, if you used a MMC which had a rootfs at offset +100 (for instance), and kept rewriting the part table + bootfs with the above command, things would just work, but as soon as you upgrade to a l-m-c with new part offset, it will create the part table pointing at a rootfs at +4000 (for instance), and will overwrite your rootfs. So I think what might help is doing a full run without --no-rootfs, then doing the next runs with --no-rootfs if you like.

I'm testing the above to see if it works.