virtio-gpu-rutabaga is another way to use a GPU from a KVM / Qemu guest which primarily Android Studio developed IIUC.

Notes re: how IOMMU GPU passthrough with device selection would be a helpful feature to add to QEMU cli, virt-manager,: https://news.ycombinator.com/item?id=46750715 :

> rutabaga_gfx does GPU paravirtualization: https://github.com/magma-gpu/rutabaga_gfx