Re: failed to resolve partition “my-root”

[Ricardo Wurmus <rekado@elephly.net>]

Ricardo Wurmus <rekado@elephly.net> writes:

> Ricardo Wurmus <rekado@elephly.net> writes:
>
>> Linux appears to boot but then fails with “failed to resolve partition
>> "my-root"”.  I suspect that something in (gnu build file-systems) is
>> broken.  koosha on IRC previously reported a similar problem.
>
> “cat /proc/partitions” shows that only the ram* devices are listed.
> None of the hard disk partitions are listed.  Also, in the rescue REPL I
> don’t see any disk under /dev/.
>
> So (gnu build file-systems) works as it should.  Curious.
>
> When I boot with the USB stick, however, /dev/sda (the USB disk) and
> /dev/sdb (the hard disk) both exist.
>
> I’m guessing that it’s a problem with the initrd; some missing kernel
> module maybe.  Is there a way to regenerate the initrd without having to
> reinstall the whole system?  I’m willing to fall back to my old ways of
> manipulating things in the store just to get this thing booted soon.
> (I’ll ask for forgiveness later.)

I fixed this by re-init-ing the system with a tiny change to the
operating system definition:

--8<---------------cut here---------------start------------->8---
  (initrd (lambda (fs . args)
            (apply base-initrd fs
                   #:extra-modules (list "sata_nv")
                   args)))
--8<---------------cut here---------------end--------------->8---

The module is needed because this is an NVIDIA disk controller.

Fixing this was tedious, though.  Before the installation I ran “guix
pull”.  When I noticed that the system would not boot I had to boot from
USB again — and then would have to run “guix pull” again.

Is there a way to avoid this?  We can’t just chroot and my attempts to
just bind mount /mnt/gnu and /mnt/var/guix after booting the disk image
from USB failed; at least when building software because the build
environment appears to fail when things are bind mounted.

I couldn’t just use Guix from /mnt/gnu, because it uses symlinks to
/gnu, which are all broken when /gnu is provided by the USB disk.

Should I have used some unionfs trickery?

Is there a “fixup recipe” we can recommend to people in the manual for
those cases where the initrd doesn’t contain the necessary kernel
modules?  Or maybe a “guix system enter /mnt” command that remounts
things and creates user accounts as necessary?

--
Ricardo

GPG: BCA6 89B6 3655 3801 C3C6  2150 197A 5888 235F ACAC
https://elephly.net