[PATCH v7 7/9] drm/virtio: Improve DMA API usage for shmem BOs

[Dmitry Osipenko]

Hello Gerd,

On 7/5/22 16:53, Gerd Hoffmann wrote:
>   Hi,
> 
>> -	 * So for the moment keep things as-is, with a bulky comment
>> -	 * for the next person who feels like removing this
>> -	 * drm_dev_set_unique() quirk.
> 
> Dragons lurking here.  It's not the first attempt to ditch this, and so
> far all have been rolled back due to regressions.  Specifically Xorg is
> notoriously picky if it doesn't find its expectations fulfilled.

I saw the previous attempt. Back then it was a mechanically created
patch that didn't get any testing.

> Also note that pci is not the only virtio transport we have.

The VirtIO indeed has other transports, but only PCI is really supported
in case of the VirtIO-GPU in kernel and in Qemu/crosvm, AFAICT. Hence
only the PCI transport was tested.

> What kind of testing has this patch seen?

The Xorg and virgl work perfectly fine in Qemu (with and without IOMMU
enabled in Qemu) and in crosvm (ChromeOS virtual machine).

-- 
Best regards,
Dmitry