Re: [Qemu-devel] [RfC PATCH 06/15] virtio-gpu/2d: add virtio gpu core code

[Gerd Hoffmann]

  Hi,

> Gerd, btw I think we mighr want to support a set scanout with no
> resource, as it might make Linux atomic modesetting easier in the
> future, we'd just scanout black.

Makes sense, and should be easy to implement.

> > However, I think it's best to simply limit ab->nr_entries to some sane value
> > (I guess it shouldn't be even in the double digits for a single resource, so
> > restricting it to 256 or something seems sane to me...) and return an error
> > to the guest if that limit is exceeded.
> 
> please be careful about limiting this, limits should be pessimistic, as if the
> the GPU allocates one page per iov, so a 1280x1024x32bpp resource will
> have 1280 iovs.

I've already picked 1024 as 256 looked a bit low to me.  Guess we should
better go for 16k instead, that is enough even for ultra hd ...

cheers,
  Gerd