NvFBC for guest to local host possible? Shared memory

[geoff@xxxxxxxxxxxxxxx]

Hi All,

I am running a KVM guest on my workstation that has a Nvidia GPU passed 
through to it. This is simply so I can run Linux and Windows with decent 
performance on the same box. It seems that all the streaming 
technologies out there are designed specifically either for low 
bandwidth remote control application, or game capture, compression and 
streaming over a network.

Since it is all on the local PC, bandwidth of a network is 
inconsequential and as such the solutions that already exist are 
sub-optimal and introduce additional latency due to encode/decode

NVidia support NvFBC (Nvidia Frame Buffer Capture) which can be used to 
capture the screen data either raw, or after encoding using h264 or h265 
to a provided block of memory.

Would it be possible to map pages of memory between the guest VM 
specifically for this purpose? and if so, could a DRI mapping be 
provided for the NvFBC API to write directly into effectively providing 
a very fast transfer of video data form guest to host?