Re: [PATCH 2/2] iommu/amd: Force identity mode for selected GPUs only

On Thu, Aug 13, 2026 at 12:11:48AM +0000, Deucher, Alexander wrote:

> > Huh? You've explained that SME doesn't work with these GPUs? How are
> > there any working systems with SME turned on already running Linux?
> 
> No one noticed it because the IOMMU driver used to default to 1:1
> mapping for all AMD GPUs that supported ATS and PRI for

That's back to the original point, you should just quirk this broken
GPU to require 1:1 and that's the right answer

I thought you had said even that does not work with SME because of
some HW reason?

Jason