[vfio-users] Differences between AMD and Intel passthrough support

[Taiidan at gmx.com]

On 11/19/2017 07:34 AM, Zycorax Tokoroa wrote:

> The issue that might have been referred to is a now (in linux 4.12 or
> 4.13) fixed bug that appeared on Ryzen while using KVM and vfio.
> Enabling or disabling nested paging in the KVM module lead to a
> deteriorated performance of either the GPU or the CPU. AFAIK Ryzen is
> now as good as Intel for hardware passthrough.
Yep.

I have a piledriver previous gen socket G34 CPU and IOMMU has always 
worked great for me as well, I play games in a VM with no issues and a 
variety of other attached devices.
It is a shame the previous gen sockets never got a CPU with AVIC I would 
say that is one of the definite advantages of AM4. (the drawback of AM4 
is that it has mandatory PSP)

FYI brian "VT-d" is an intel marketing term for IOMMU - AMD's is AMD-Vi 
- but to make it easy I always refer to it as IOMMU and the graphics 
support option as IOMMU-GFX.