[Top][All Lists]

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

[Qemu-devel] Re: [PATCH] Add VirtIO Frame Buffer Support

From: Alexander Graf
Subject: [Qemu-devel] Re: [PATCH] Add VirtIO Frame Buffer Support
Date: Tue, 3 Nov 2009 08:50:13 +0100

On 03.11.2009, at 08:43, Avi Kivity wrote:

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?

Ok, imagine this was not this unloved S390 odd architecture but X86. The only output choices you have are:

1) virtio-console
2) VNC / SSH over network
3) virtio-fb

Now you want to configure a server, probably using yast and all those nice graphical utilities, but still enable a firewall so people outside don't intrude your machine. Well, you managed to configure the firewall by luck to allow VNC, but now you reconfigured it and something broke - but VNC was your only chance to access the machine. Oops...

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.

It doesn't do graphics. Ever used yast in text mode?

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).

Yes, we do that. Still doesn't buy you graphics.

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.

The vmware-port stuff is pretty much tied onto X86. I don't think modifying EAX is that easy on PPC ;-).

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.

You can't hide guest configuration. We as a distribution control the kernel. We don't control the user's configuration as that's by design the user's choice. The only thing we can do is give users meaningful choices to choose from - and having graphics available is definitely one of them.

Seriously, try to ask someone internally to get access to an S390. I think you'll understand my motivations a lot better after having used it for a bit.


reply via email to

[Prev in Thread] Current Thread [Next in Thread]