I created a reddit post but also will place one here. PCI Passthrough is completely broken on threadripper and the X399 platform. There is not a single case reported of being succesful. The tech reviewer who was supposed to post a video showing it has been radio silent. I can't believe we have to deal with 0day support when a MAJOR use case of threadripper is to have plenty of VM's.
Will provide any information necessary if we have dev cooperation but I'll be RMA'ing at the end of my 30 days if theres no patch in place.
That's why I usually wait 2 years b4 jumping on new hardware designs - this is sufficient time to patch hardware errata.
I have this issue as well. Due to it and other issues, my Threadripper build has been a giant unmitigated disaster unfortunately. I was extremely excited to do this build. I had hyped up the possibilities that all the cores offered specifically with VMs, Pass-through, Compilation, etc to everyone I knew, and they'd all be anticipating seeing how it turns out. Unfortunately, I had to report to them that my build has been a complete failure due to this.
For a high-end part @ $999 and affiliated motherboard (Zenith) @ $549, this is not acceptable. If I had bought the Core i9 instead, I would not be having this issue. If I go back to my older i7, I don't have this issue. I want to give Team AMD a chance as I appreciate what you guys are doing to up the available core count, but the parts have to work.
Several things greatly concern me right now after I've looked into it further that I am looking for AMD to address:
None of these issues are problems on Team Intel. I want to give Team AMD a chance again... I really do. The Threadripper has amazing potential if the issues are fixed, and makes the price much more affordable. But again, the features required to utilize them have to work. Like the original poster, if I don't see both recognition and traction from AMD on these issues soon, then I will be RMA'ing as well at the end of the window and going with the Core i9. I hope that AMD takes these issues seriously and starts to get fixes in place. Especially because, since you're using the same architecture for Epyc, those processors are going to have a hard time in the server market with things like this broken.
With that said, on to information about this issue. Here is what I've collected from my motherboard. Please pass on to engineering:
Versions tried (same result on all of them):
I have the exact same problem.
If I use pci=nommconf in grub, the iommu groups are all bunched up together.
Motherboard is an Asrock X399 Fatality professional gamer (wierd name for a workstation board!).
You can also add USB controllers with Fresco Logic chipsets to the "not compatible" list. System will not POST with it installed (chipset init failed).
Yep, that's what my Inateck USB PCIe is. I reported that to Asus on their forums and another user confirmed the issue there as well.
I reported the issue to Asrock last week, but have not heard back from them yet.
So far am in the same boat as you, I need IOMMU and passthrough to work otherwise I have to RMA the whole build :-/
Edit: Asrock replied, usual test all the slots, test in another machine etc.
I find the lack of official replies overwhelmingly disappointing. To be honest, time is running out on my 30 day open return thing.
Agreed. I filed a support ticket pointing to this (and the other) threads - hopefully that will draw some attention. I want to like the Threadripper and really appreciate what AMD is trying to do by getting higher core counts more affordable, but the parts gotta work.