Re: [libvirt] [PATCH 0/3] sample: vfio mdev display devices.
On Thu, Apr 26, 2018 at 03:44:15AM +0000, Tian, Kevin wrote:
> From: Alex Williamson
> Sent: Thursday, April 19, 2018 2:32 AM
>
> That almost begins to look reasonable, but then we can only expose this
> for mdev devices, what if we were to hack a back door into a directly
> assigned GPU that tracks the location of active display in the
> framebuffer and implement the GFX_PLANE interface for that? We have no
> sysfs representation for either the template or the actual device for
> anything other than mdev. This inconsistency with physically assigned
> devices has been one of my arguments against enhancing mdev sysfs.
One possible option is to wrap directly assigned GPU into a mdev. The
parent driver could be a dummy PCI driver which does basic PCI
initialization, and then provide hooks for vendor-specific hack.
Thowing amdgpu into the mix. Looks they have vgpu support too, but
using sriov instead of mdev. Having VFIO_GFX support surely looks
useful there. Adding a mdev dependency to the VFIO_GFX api would makes
things more complicated there for (IMHO) no good reason ...
cheers,
Gerd