Re: [PATCH v2] iommu/amd: Set translation valid bit only when IO page tables are in used

From: Joerg Roedel
Date: Fri May 20 2022 - 04:59:03 EST


On Fri, May 20, 2022 at 09:54:51AM +0100, Robin Murphy wrote:
> The .def_domain type op already allows drivers to do exactly this sort of
> override. You could also conditionally reject IOMMU_DOMAIN_PASSTHROUGH in
> .domain_alloc for good measure, provided that (for now at least*) SNP is a
> global thing rather than per-instance.

Yeah, that could work. I am just not sure the IOMMU core behaves well in
all situations when allocation IOMMU_DOMAIN_PASSTHROUGH suddenly starts
to fail. I would feel better if this is checked and tested :)

Regards,

Joerg