grub2, cannot upgrade due to EFI partition type mismatch

[Gianfranco Costamagna]

grub2, when looking for suitable ESPs, only looks at MBR partitions with id 0xef. However, systems do boot from other vfat partitions too, in this case, a 0xb partition.

Now, if the ESPs were changed while upgrading, the prompt to select ESPs will not be shown and the upgrade will fail; because no ESPs are considered valid and hences CHOICES is empty.

IRC discussion: https://irclogs.ubuntu.com/2020/10/12/%23ubuntu-devel.html

Trace log: Attached
Workaround: Change partition type of /boot/efi or other ESPs from 0xb (in this concrete example) to 0xef

[Gianfranco Costamagna (costamagnagianfranco)]

Here another (little different) failure log

[Brian Murray (brian-murray)]

The Groovy Gorilla has reached end of life, so this bug will not be fixed for that release

[Mate Kukri (mkukri)]

Since this is ESP on MBR only problem (which isn't exactly a thing we do nowdays), I don't think SRU-ing this is worth it, but I'll look at whether or not Oracular still needs this fixed.