I have an Ubuntu Server 12.10 setup with Xen 4.2.0 installed (compiled from source) and an AMD Radeon 7750 GPU. My Xen installation appears to be working and I can create virtual machines for example.
I have set up a virtual machine and it appears to be working fine when connecting to it with VNC. However, after changing the config to enable GPU passthrough, nothing is appearing on my monitor and VNC just displays "serial0" and does not allow me to do anything.
In order to enable GPU passthrough I appended the following to my config file:
gfx_passthru=1
pci=['01:00.0']
How can I pass my GPU to my virtual machine properly?