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Date: Thu, 8 Sep 2022 15:30:09 +0200
From: Joerg Roedel <joro@8bytes.org>
To: Jason Gunthorpe <jgg@nvidia.com>
Cc: Robin Murphy <robin.murphy@arm.com>,
	Vasant Hegde <vasant.hegde@amd.com>, iommu@lists.linux.dev,
	suravee.suthikulpanit@amd.com
Subject: Re: [PATCH v3 0/9] iommu/amd: Add Generic IO Page Table Framework
 Support for v2 Page Table
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References: <20220825063939.8360-1-vasant.hegde@amd.com>
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 <YxjMQpGYaHfsiuL+@nvidia.com>
 <YxneJ2RqaatKmoYT@8bytes.org>
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In-Reply-To: <Yxnr1gBIGwdinIkr@nvidia.com>

On Thu, Sep 08, 2022 at 10:19:18AM -0300, Jason Gunthorpe wrote:
> What is the use case for having PASID nested under another level of
> translation?

Virtualization. Basically having a device access process address spaces
inside a virtual machine. That got never put into code, but it was the
rationale behind it.

Regards,

	Joerg