Re: [PATCH] Add VirtIO Frame Buffer Support

Avi Kivity
2009-11-03T07:44:03Z

On 11/03/2009 08:39 AM, Alexander Graf wrote:
>
> On 03.11.2009, at 07:34, Avi Kivity wrote:
>
>> On 11/03/2009 08:27 AM, Alexander Graf wrote:
>>>
>>>> How does it work today?
>>>
>>> You boot into a TERM=dumb line based emulation on 3270 (worst thing
>>> haunting people's nightmares ever), trying to get out of that mode
>>> as quickly as possible and off into SSH / VNC.
>>
>> Despite the coolness factor, IMO a few minutes during install time do
>> not justify a new hardware model and a new driver.
>
> It's more than just coolness factor. There are use cases out there
> (www.susestudio.com) that don't want to rely on the guest exporting a
> VNC server to the outside just to access graphics.

Instead you rely on the guest using virtio-fb. Since we have to make
guest modifications, why not go for the simpler ones?

> You also want to see boot messages, have a console login screen,

virtio-console does that, except for the penguins. Better, since you
can scroll back.

> be able to debug things without switching between virtio-console and
> vnc, etc. etc.

Render virtio-console on your vnc session. We do that already, no?
(well, the host's vnc session, not the guest's).

> The hardware model isn't exactly new either. It's just the next
> logical step to a full PV machine using virtio. If the virtio-fb stuff
> turns out to be really fast and reliable, I could even imagine it
> being the default target for kvm on ppc as well, as we can't switch
> resolutions on the fly there atm.
>

We could with vmware-vga.

>>
>> Why? the guest will typically have networking when it's set up, so
>> it should have network access during install. You can easily use
>> slirp redirection and the built-in dhcp server to set this up with
>> relatively few hassles.
>
> That's how I use it right now. It's no fun.
>

The toolstack should hide the unfun parts.

--
Do not meddle in the internals of kernels, for they are subtle and quick to panic.