Sorry, I did not intend to be rude. My point was that it is a known problem with a known solution (albeit for a different code base).
I would love to take have a go with implementing a patch. Unfortunately at this time I do not posses neither the hardware, nor the knowledge or time to do it (day job and family).
Otherwise I agree with @Biggen. This is a really niche use case and not many people are interested in it, therefore it is not considered important. Thanks for putting it in a more understandable way mate.
It just sucks to be on the minority side I guess.
P.S. @olivierlambert Are you saying that there are no plans for implementing a patch for this in the future?
@Biggen as far as I know only vGPU enabled cards (Grid/Tesla) do not have this problem, and even so those cards require crazy subscription-based licenses to work. We are talking about sums that only enterprise data centers can afford. Furthermore, even if you have a Tesla card + license you still cannot do a PCI pass trough - you are limited to assigning "slices" (vGPUs) to the VMs + you need a proprietary driver on the host for that to work and such does not exist for XCP-NG.
Consumer, Titan... PCI passthrough = code 43 (unless you find a way to trick the drivers to think they are not running in a VM). I read mixed reports about Quadro, so I would say that those are a hit or miss, depending on the card and driver used. About the drivers themselves - basically older drivers are more likely to work and by older I mean downloaded in the past older drivers. I read complaints in other forums saying "driver XXX worked before but when I downloaded it now it does not work anymore" so my guess is that they have recompiled the older drivers to include the code 43 error.