Re: [gentoo-user] Boot and EFI partitions

[Wols Lists <antlists@youngman.org.uk>]

On 06/12/2023 16:36, Jack Ostroff wrote:
> The way I think of it is that the UEFI firmware needs to find the 
> xxxx.efi loader, and it can only read FAT32 formatted partitions 
> labelled as type esp. That xxxx.efi loader then needs to find your 
> kernel and related files, but as it is specific for that type of kernel 
> (linux) it can know about more partition formatting options. I suspect 
> that many (most?/all?) existing linux utilities still expect the boot 
> dir to be at /boot, but perhaps the docs are late to change describing 
> that it no longer needs to be a separate partition, or perhaps one or 
> more of those utilities still requires a partition.

It's not that far off base ... note that Macs use UEFI, but don't have 
FAT32 partitions ...

On the raid wiki I say that you need *some* sort of boot partition, and 
say that if you're using legacy (bios) boot you should really put /boot 
on its own partition so if you decide to go UEFI, you re-purpose that 
partition. It certainly seems weird that systemd-boot would want its own 
partition on top of the efi partition :-)

The UEFI spec basically requires - as a minimum - that the UEFI software 
in rom must be able to read fat32. There is no requirement that that is 
the only format it can read, hence Macs reading the Mac format. If you 
want your own boot rom that can read ext*, that's fine (so long as ext32 
is also available).

Cheers,
Wol