Re: libvirt with modified QEMU and OVMF

[Lars Böckel]

Thanks for sharing your idea about it. I cannot pull right now but i 
think ...nvram = " ovmf "/F... would not work since you would have to 
call the complete path of the package. Though something like "nvram = 
/run/current-system/profile/share/firmware/ovmf_x64.bin" COULD work. I 
don't know how it would react to the massive wall of symlinks. That is 
probably the reason why NixOS calls it with ${pkgs.OVMF}. The produced 
file in NixOS (/var/lib/libvirt/qemu.conf) points to /nix/store/....
For usability something you can just put in libvirt-service-type with #t 
would be good for usability. As well as the user variable. 
Configurations like these are probably more common than changing 
tls-ports and would simplify the migration of people running different 
systems since they could more easily configure VMs with UEFI support.

When my internet is running again i will pull and try this config. But 
since its saturday that might take some time... You can easily check for 
UEFI support in libvirt with either virt-install --boot uefi or in 
virt-manager when you create a vm and edit it beforehand you have a 
dropdown menu for BIOS/UEFI. If someone could test it out and report 
back that would be great!


> > i would like to push the issue with OVMF in libvirt again:
> >
> > I would like to have OVMF(UEFI) capability with QEMU. In NixOS you can
> > achieve this with
> >
> >    virtualisation.libvirtd.enable = true;
> >    virtualisation.libvirtd.qemuOvmf = true;
> >     virtualisation.libvirtd.qemuVerbatimConfig = ''
> >       nvram = [ "${pkgs.OVMF}/FV/OVMF.fd:${pkgs.OVMF}/FV/OVMF_VARS.fd" ]
> >       user = "1000"
> >     '';
> >
> > the "user" part is not necessary but is required for system VMs in
> > combination with qemu's pulseaudio driver. qemuVerbatimConfig is the
> > config that is at /etc/libvirt/qemu.conf in traditional GNU/Linux
> > distributions.
> I don’t know about OVMF but IIUC, what you need here is to create
> /etc/libvirt/qemu.conf.  To do that, you can something along these
> lines:
>
>    (simple-service 'qemu-conf etc-service-type
>                    `(("libvirt/qemu.conf"
>                       ,(mixed-text-file "qemu.conf"
>                                          "nvarm = "
>                                          ovmf "/FV/OVMF.fd:…'))))
>
> Would that work?
>
> (Actually the “libvirt/” bit is only possible since commit
> 5dec93bb8ba89605bce2f9a5ee9c4dbadeee3b58, a few minutes ago…)
>
> We could provide a proper abstraction on top of that if needed, but I’m
> not familiar with libvirt.  If you have ideas on how to improve this,
> that’d be great!
>
> Thanks,
> Ludo’.