Comment 48 for bug 1097570

It's a bit hard to make sure I'm hitting all the right cases, but it did look (with a fairly recent grub) like searching was unnecessary. This would make the changes pretty small.

Shih-Yuan, could you try out a fixed-up grub2-signed image if I provide you with the right files for it? It would require at least replacing the grubx64.efi file on the EFI partition on a USB key. For a CD, it means re-building the CD with the right embedded images, something which seemed to be failing here. I'll prepare a new image for Trusty now and give rebuilding the CD another try (if it works, then I'll just get you an ISO image to use for testing)