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Date:   Tue, 15 Feb 2022 10:45:24 -0400
From:   Jason Gunthorpe <jgg@nvidia.com>
To:     David Hildenbrand <david@redhat.com>
Cc:     Felix Kuehling <felix.kuehling@amd.com>,
        Alex Sierra <alex.sierra@amd.com>, akpm@linux-foundation.org,
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Subject: Re: [PATCH v6 01/10] mm: add zone device coherent type memory support
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On Tue, Feb 15, 2022 at 01:16:43PM +0100, David Hildenbrand wrote:
> > fact, the first version of our patches attempted to add migration 
> > support to DEVICE_GENERIC. But we were convinced to create a new 
> > ZONE_DEVICE page type for our use case instead.
> 
> Do you know if DEVICE_GENERIC pages would end up as PageAnon()? My
> assumption was that they would be part of a special mapping.

We need to stop using the special PTEs and VMAs for things that have a
struct page. This is a mistake DAX created that must be undone.

Jason