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Date: Wed, 7 Sep 2022 16:16:20 +0200
From: Joerg Roedel <joro@8bytes.org>
To: Robin Murphy <robin.murphy@arm.com>
Cc: Vasant Hegde <vasant.hegde@amd.com>, iommu@lists.linux.dev,
	suravee.suthikulpanit@amd.com, Jason Gunthorpe <jgg@nvidia.com>
Subject: Re: [PATCH v3 0/9] iommu/amd: Add Generic IO Page Table Framework
 Support for v2 Page Table
Message-ID: <YxintMDEmzSXJUl5@8bytes.org>
References: <20220825063939.8360-1-vasant.hegde@amd.com>
 <77d2ea43-9752-b5f3-78ef-8cdae944eee4@amd.com>
 <05f9784b-15b6-2a9b-2d9e-19e1430f74e2@arm.com>
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In-Reply-To: <05f9784b-15b6-2a9b-2d9e-19e1430f74e2@arm.com>

On Tue, Sep 06, 2022 at 05:35:13PM +0100, Robin Murphy wrote:
> Will this series also mean that the domain shenanigans in
> amd_iommu_init_device() can be replaced by just making sure the GPU gets the
> proper type of v2 default domain in the first place, so KFD can use its
> PASIDs on top of that directly, and the audio driver problem goes away
> naturally?

Yes, on IOMMUs supporting v2 page-tables and declaring a default PASID
this hack can go away. Unfortunately a lot of AMD IOMMUs in the field do
not, so the identity mapping hack needs to stay around.