Re: installation on LVM on LUKS

[Emmanuel Beffara <manu@beffara.org>]

De wolf le 04/03/2023 à 00:42:
> On 2023-03-03 18:03:39 +0100, Emmanuel Beffara wrote:
> > Unless I am missing something, tinkering with initrd modules has nothing to do
> > with my issue. The missing “insmod lvm” is in grub.cfg, it is related to Grub
> > modules, not kernel modules. The required modules for Grub are properly
> > installed in /boot/grub (I mount the EFI partition as /boot), it is just that
> > the generated configuration file does not load enough of them.
> 
> Maybe that is the problem? For me it works out of the box, but I have EFI
> mounted as /boot/efi. Could you maybe either try to do that as well,

I just tried that: mounting the EFI partition in /boot/efi instead of /boot
and adujsting the config.scm accordingly (the entry for /boot/efi in
file-systems and the target for grub). I also cleaned everything there that
was installed by Guix (the Guix folder, the grub folder). Turns out that this
way, the system just cannot start. In the EFI partition, there is
EFI/Guix/grubx64.efi but running this leads to an error:

	error: disk 'lvmid/(the UUID of the root fs)' not found.
	Entering rescue mode...

I cannot do much in this recue mode. Of course Grub cannot find the partition
since its modules for LUKS and LVM are now stored in the system's root
partition under /boot, encrypted…

I'm surprised that it works for you out of the box given what I observe. Where
are Grub's modules stored ? Is the installed EFI binary somehow able to
decrypt the partition and its LVM contents without loading modules for that ?

> or (untested idea I just had) provide (dependencies mapped-devices) for the
> /boot mount point as well (I know, it is not technically required)?

I also tried that and it does not change anything.

> I am using 64M EFI partition, so I could imagine that filling up, especially if
> one does not clean up the generations very often. Since increasing the EFI size
> could be impossible without reinstall, if this is done, it should likely be
> opt-in only.

Certainly.

-- 
Emmanuel