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Date:   Fri, 20 May 2022 10:58:53 +0200
From:   Joerg Roedel <joro@8bytes.org>
To:     Robin Murphy <robin.murphy@arm.com>
Cc:     Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>,
        iommu@lists.linux-foundation.org, jon.grimm@amd.com,
        linux-kernel@vger.kernel.org, vasant.hegde@amd.com
Subject: Re: [PATCH v2] iommu/amd: Set translation valid bit only when IO
 page tables are in used
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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