This is just a short update detailing my frustrations with some of the more complex functions that QEMU/KVM Virtualization has to offer.
I've spent the better part of two days playing with GPU Passthrough on my Skylake system again. I wrote the book (literally) on passthrough about a year ago, but in that year, either I've gotten worse or VFIO and QEMU have gotten more finickey.
The more I think about the status of Passthrough, the more mixed feelings I get about it. We've come a long way on the software side, but it seems we're regressing a lot on the hardware compatibility side of things. A short (maybe not) 5 years ago, we had hardware that fully supported bus resets, we had less advanced detection of Virtual Machines on the Nvidia (driver) side. In short, we had hardware that was waiting to be unleashed.
Recently, we've had major hardware issues, particularly on the AMD side. AMD has made some incredible steps to get back in the game on the CPU side of things, no doubt, but at the same time, we had a few problems. AMD has always had a problem with Nested Page Tables, since fixed, but the more pressing issue is the Radeon Bus reset issue that's plagued all R9 GPUs and Vega. This means that if you want to use Team Red GPUs, you're pretty much locked out of 4k gaming in a VM.
On the topic of Intel. X299 seems to be a good solution at the moment, but the major problem with it right now is the cost. To get the equivalent of a $1700 Threadripper system, you're going to have to shell out as much for the processor alone. Nevermind the Motherboard, RAM, and other components. I've never been a huge fan of Intel, but the do have the best solution if money is no object.
The grass may seem a bit greener on the other side though, with Nvidia GPUs only being intentionally disabled by the manufacturer if they detect the presence of VM extensions. At this point, I'm not really sure what I can say that hasn't already been said. Nvidia is doing this to justify the sale of their Quadro GPUs, which are definitely good, but the price is outrageous for people who just want to play some games.
I'm not really sure what else there is to say. I'm in the process of hammering out the problems on my GPUs, but the access I have to hardware is quite limited at the moment, considering I haven't yet bought into the latest generation AMD hardware. Hopefully, these companies will pull their heads out of their collective asses and we'll have a solution that will just work. I'd love to get behind a certain manufacturer right now, but at the moment, we're going nowhere fast on all fronts.