bug#44872: Installer crash: 'uuid->string' is passed #f in lieu of a UUID

[Mathieu Othacehe <othacehe@gnu.org>]

Hello David,

>> I'm using manual partitioning with the first partition mounted as the
>> ESP partition and the sixth partition as the root directory.

My issue here is that those partitions were never formatted. The
read-partition-uuid method returns #f on unformatted partitions, causing
the installer crash.

I fixed this issue with f5d9d6ec68f78f5651bd5a698f489ab57bf77d5d. The
rationale is that any partition that will be mounted and not formatted
("Format the partition? No) must have a valid UUID. The installer
now prevents going further if this is not the case.

That said, I think you are experiencing a different issue. The REPL
commands you ran show that your nvme0n1p1 and nvme0n1p6 partitions have
valid UUIDs.

That's why I also pushed this commit:
1a0a18d0ccc6cb6c7f4e42a0d659340f13b206c5 that prints in the syslog the
internal <user-partitions> list, hoping that it will help us understand
what's going on.

It would be great if you could build a new installer image on top of
master, try reproducing the crash and attach the content of the
"/var/log/messages" file. You can for instance scp it to another machine
of your local network running an SSH server.

I'm not sure if you are aware of this feature, but generating
uncompressed ISO9660 image is a serious time saver when debugging the
installer:

--8<---------------cut here---------------start------------->8---
guix system image -t uncompressed-iso9660 gnu/system/install.scm
--8<---------------cut here---------------end--------------->8---

Thanks,

Mathieu