I have my system (Thinkpad P52, 20M90019RT) with iGFX and Nvidia P2000 configured to run with PRIME render offload using libglvnd.
When I try to run a KVM virtual machine with gvt-g, the VM process is killed with segfault when mouse enters the VM window. Naturally, my first suspect was gvt-g so I opened the issue there https://github.com/intel/gvt-linux/issues/162 . After some investigation by the gvt-g developers they suggested to test without PRIME render offload configuration (by blacklisting the autoloading of nvidia kernel modules) and the issue went away.
I kindly encourage you look thru the issue as gvt-g developer suggested that nvidia driver is taking too much “initiative” and spoils the dma-bufs of the mediated device. I don’t understand much of the way both technologies work, I’m a mere user in need of both render offload and gvt-g on my laptop.
thanks for looking into it.