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's slides mention the ability to accelerate up to '8 VMs plus DOM0'. Source: https://01.org/sites/default/files/documentation/an_introduction_to_intel_gvt-g_for_external.pdf

Intel currently supports host DRM and VFIO-Mdev functionality in it's i915 driver sources.

Known Issues

1. SR-IOV functionality is undocumented in the i915 driver API documentation.
   Confirmed affected versions: *
2. GVT-g functions require use of KVMGT/XenGT (forked from mainline)
   Confirmed affected versions: *
   

   A diagram depicting i915's shared host + VFIO-Mdev driver model.

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

1. 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
   Possible mitigation (lore.kernel.org vfio/pci power management patch): "vfio/pci: Change the PF power state to D0 before enabling VFs"
2. 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

At this time AMDGPU does not currently support VFIO-Mdev functionality. It may be possible to incorporate RPC Mode mediated device support similar to those functions in nvidia.ko and i915.ko in the Linux kernel's AMDGPU driver sources to produce a driver suitable for merged host+guest DRM for use with AMD GPU devices.

Known Issues

1. Host DRM does not work alongside guest VFIO-Mdev.
   Confirmed affected versions: *
2. Hardware accelerated encoding/decoding via GPU-IOV Module (GIM) does not work.
   Confirmed affected versions: 3.0