Has anyone tried multiseat with Ryzen GPU passthru?

Not to be confused with multihead, specifically I’m talking about having two or more VMs each with it’s own GPU (and mb/mouse and monitor).

The famous 7 gamers 1 cpu video is an example of this.

I’m asking because I have several X58 boards that work great with one VM, but when a second VM is started the GPU drivers will crash sooner rather than later, and I’m worried that this will be an issue again.

(The exception to this is if all VMs and their virtual disks are stored on the same disk as root, which is a less-than-ideal setup.)

Also, I’ve read in a few places that vt-d is not as well supported by AMD as with Intel, but invariably no specifics are ever given and the author does not sound so sure of him or herself.

If I can ask a second question in the same thread: does anyone know if this is based in fact, and if so could anyone elaborate on the difference? The issue with concurrent VMs notwithstanding, I can attest that passthu seems to work very well on my current platform.

the divers for the guest machines crash? That seems weird. Are you having to apply the ACS patch to fake the IOMMU groupings?

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No. It appears to be some issue with interrupts on what is 1st gen hardware for iommu.

I got an X399 system together yesterday, but it stopped posting before I got finished setting up .

Hopefully this works better after o resolve the immediate posting problem.

For posterity:

Turns out IOMMU is broken on TR, but as luck would have it, it appears a fix is at hand: