Support WDDM 1.3 and embedded display in qxl-wddm-dod for an Optimus Windows guest hybrid setup

Submitted by obl..@..il.com

Assigned to Spice Bug List

Link to original bug (#106760)

Description

There have been progress to get an Nvidia dGPU to work in a Windows guest in an Optimus setup for the past year. A hacky OVMF patch [1] has allowed the dGPU to initialize properly, bypassing the error 43, and allowed certain applications to make use of the dGPU at a near-native performance.

However, the number of applications that are clever enough to make use of the dGPU seem rare. A reason for this could be due to a lack of proper hybrid setup where an integrated/embedded display panel is not detected.

A potential solution to this could be to modify the qxl-wddm-dod driver to WDDM 1.3 and expose the emulated display as an embedded display. [2,3,4]

[1] https://github.com/jscinoz/optimus-vfio-docs/issues/2 [2] https://github.com/jscinoz/optimus-vfio-docs/issues/2#issuecomment-390550145 [3] https://www.redhat.com/archives/vfio-users/2018-April/msg00019.html [4] https://reddit.com/r/VFIO/comments/8gv60l/current_state_of_optimus_muxless_laptop_gpu/