[vfio-users] Is there a way to fake subsystem id for passthrough cards?

[Alex Williamson]

On Thu, 11 Jan 2018 00:49:57 -0800
Nick S <nick.kvmhv at gmail.com> wrote:

> I have several cards of the same model that I use for different VMs and
> each time I move a virtual machine from one GPU to another that VM
> apparently goes through a driver re-installation routine. The only
> difference between cards appears to be Subsystem ID. Is there a way to fake
> it somehow? I.E. by patching one of the host kernel modules? I am running a
> customized kernel anyway, so patching it a bit more wouldn't be an issue.
> Any pointers where it can be patched (if it can) will be much appreciated!

$ qemu-system-x86_64 -device vfio-pci,? 2>&1 | grep "x-pci-.*-id"
vfio-pci.x-pci-sub-device-id=uint32
vfio-pci.x-pci-vendor-id=uint32
vfio-pci.x-pci-device-id=uint32
vfio-pci.x-pci-sub-vendor-id=uint32

Since QEMU 2.5