[vfio-users] Not binding GPU to vfio-pci

[Alex Williamson]

On Sat, 20 Feb 2016 18:47:29 -0500
Nick Sarnie <commendsarnex at gmail.com> wrote:

> Hi guys,
> When i want to do gpu-passthrough, i just unbind my GPU from radeon, and
> then pass it to qemu. I don't bind it to vfio-pci or any driver and it
> works fine. Is there any downside or performance loss to doing it this way?

Does this mean you're using the pci-assign driver with qemu?  If so, be
advised that legacy KVM device assignment is deprecated upstream, so it
will likely go away at some point and it mostly unsupported already.
Generally it's advised to avoid host drivers because they don't like
releasing devices and things like Xorg get unhappy as well.  If you
have a usage model that allows you to release the device, go for it,
but you probably want to migrate away from legacy KVM device
assignment.