Comment 11 for bug 228744

Well, guessing the filesystem size is not a problem. In fact, u-v-b *defines* the filesystem size in the end anyway. We just do all the work in a separate directory first and the move it into the loop-mounted filesystem images so that temporary files won't use up file system blocks and bloat the resulting filesystem images. If we stopped doing that, this would all be solved. I'll see if I can come up with a patch. The current approach is certainly wrong.