[libvirt] [PATCH v2 00/15] Firmware auto selection

[Michal Privoznik]

On 3/7/19 1:04 PM, Daniel P. Berrangé wrote:
> On Thu, Mar 07, 2019 at 10:29:10AM +0100, Michal Privoznik wrote:
>> v2 of:
>>
>>    https://www.redhat.com/archives/libvir-list/2019-February/msg01503.html
>>
>> As usual, you can find my patches at my github:
>>
>>    https://github.com/zippy2/libvirt/commits/firmware_v2
>>
>> diff to v1:
>> - Hopefully all Lazlo's comment are worked in (fixing the logic that
>>    chooses suitable firmware for secboot/SMM domains, commit message
>>    adjustements, sanity check for parsed FW descriptions, etc.)
>>
>> - Added more debug messages around FW selection code, i.e. it'll be
>>    visible from the logs why given FS is not suitable (or that it is).
> 
> I've done a very quick review of the patches and the design and
> overall implementation strategy looks good to me. A few misc
> points
> 
>   - We ought to expose the list of firmware types supported
>     in the domain capabilities, so mgmt apps can probe if
>     uefi is available

Makes sense, I'll start working on this after these are merged.

> 
>   - What should we do about the 'nvram' config from /etc/libvirt/qemu.conf
>     We can't get rid of it for a while, since the new firmware configs
>     won't be widely supported by distros in forseeable future. In the
>     places which currently use the 'nvram' config though, should we
>     make sure we consult the firmware configs in prefereence to
>     resolve the var store ?  Maybe your code is already doing this and
>     I missed the logic from the diffs.

I think we can ignore 'nvram' from qemu.conf safely. The whole point of 
nvram variable is to define which varstore corresponds to which fw 
image. These pairs are consulted if and only if no template was 
specified in domain XML. With firmware autoselect I don't think we are 
going to fulfil the condition as my code takes whatever FW config said 
the path to NVRAM is and uses that as template for the domain.
And even if FW config did not provide any NVRAM path (which can be 
viewed as bug IMO) then we would consult qemu.conf (or some hardwired 
defaults).

> 
>   - We support 'bios' and 'efi' right now, but QEMU also reoprts
>     'openfirmware' and 'uboot' as supported types. In practice
>     no config files probably exist for those yet, but if it is
>     easy to make the code support them we should try todo it to
>     get parity with the QEMU spec

Sure. It's just that I don't think there is a way to even configure thos 
via our domain XML, is there?

> 
> I don't think any of these are blockers though - all would work
> as followup patches I expect.

Yes, agreed.

Michal