Re: [PATCH v18 0/6] drm/i915/gvt: Dma-buf support for GVT-g

[Alex Williamson]

On Wed, 15 Nov 2017 11:49:00 +0100
Gerd Hoffmann <kraxel@xxxxxxxxxx> wrote:

> On Wed, Nov 15, 2017 at 05:11:49PM +0800, Tina Zhang wrote:
> > v17->v18:
> > 1) unmap vgpu's opregion when destroying vgpu.
> > 2) update comments for VFIO_DEVICE_GET_GFX_DMABUF. (Alex)  
> 
> > This patch set adds the dma-buf support for intel GVT-g.
> > 
> > dma-buf is an uniform mechanism to share DMA buffers across different
> > devices and subsystems. dma-buf for intel GVT-g is mainly used to share
> > the vgpu's framebuffer to userspace to leverage userspace graphics stacks
> > to render the framebuffer to the display monitor.
> > 
> > The main idea is that we create a gem object and set vgpu's framebuffer as
> > its backing storage. Then, export a dma-buf associated with this gem object.
> > With the fd of this dma-buf, userspace can directly handle this buffer.
> > 
> > This patch set can be tried with the following example:
> > 	git://git.kraxel.org/qemu  branch: work/intel-vgpu
> > 
> > A topic branch with the latest patch set is:
> >         https://github.com/intel/gvt-linux.git   branch: topic/dmabuf  
> 
> Tested-by: Gerd Hoffmann <kraxel@xxxxxxxxxx>

Hi Gerd,

Can you share the xml snippets required for the VM to make this work?
Last I tried I couldn't get the display/video/hostdev configuration to
get any enhanced behavior through the dmabuf.  Thanks,

Alex