Merged Drivers
The following page will provide specifications and details on the current state of host DRM + VFIO-Mdev drivers in support of various vendors.
Intel i915

Intel currently supports host DRM and VFIO-Mdev functionality in it's i915 driver sources.
Nvidia
For more information on host DRM and VFIO-Mdev support on Nvidia drivers refer to section 6 of the vGPU Community Wiki.
Known Issues
-Power management on laptops running mediated graphics functionality may causes graphical errors when not plugged in to AC power.
Confirmed affected versions: 460.32.01, 460.73.04
-VFIO-vmalloc errors may occur as a result of page collisions between host & guest on GPUs with smaller VRAM frame buffer sizes.
Confirmed affected versions: 460.32.01, 460.73.04
AMDGPU + GPU-IOV Module Merged
At this time AMDGPU does not currently support VFIO-Mdev functionality. It may be possible to merge the GPU-IOV Module (GIM) sources with the Linux kernel's AMDGPU driver sources to produce a merged driver for use on AMD GPUs.