Re: [PATCH 0/2] Bli: fix hidden module dependency

[Daniel Kiper]

On Wed, Nov 15, 2023 at 03:12:44AM -0800, Oliver Steffen wrote:
> Quoting Vladimir 'phcoder' Serbinenko (2023-11-14 19:21:49)
> > In general series looks good. Few comments:
> > * I'm unsure about the name. It seems to suggest that people put the
> > dependencies there by default while in fact it's the last place for it. 
> > Maybe
> > extra_deps.lst?
> >
> Sounds good to me.
>
> Are we ok with the '.lst' extension? Files of this type are listed in
> .gitignore and this would be an exception.

I think we can live with lst extension if we do not come up with
something better.

> > * EFI supports both GPT and msdos. GPT is a more common choice but I still
> > think that a dependency on part_msdos is warranted
>
> bli does not make use of msdos partitions. It ignores them.
>
> bli implements a small part of the Boot Loader Interface spec [1], by
> setting some EFI variables that are later consumed by systemd. One of
> them contains the GPT UUID of the ESP/the partition used during boot.
> This is needed to make systemd's partition autodetection work [2,3]. All
> of this is build around GPT and uses the UUIDs of GPTm and does not work
> with msdos formatted disks.
>
> [1] https://systemd.io/BOOT_LOADER_INTERFACE/
> [2] 
> https://www.freedesktop.org/software/systemd/man/systemd-gpt-auto-generator.html
> [3] 
> https://uapi-group.org/specifications/specs/discoverable_partitions_specification

I expected that Boot Loader Interface does not use MBR at all and rely
entirely on GPT. However, I think we should make it clear in the GRUB
documentation to avoid complaints/confusion/... in the future. Oliver,
could you add relevant blurb to docs?

> > * Please elaborate commit message as to why bli needs those mods rather than
> > "not functions properly". Detail that it needs to identify partitions.
>
> I can do that.
> bli tries to read the UUID of the ESP/the partition Grub was loaded
> from. If that is not GPT or otherwise not reachable, then it does not
> set the corresponding EFI variable, but c

Yeah, more or less like that makes sense for me.

Daniel