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Date:   Wed, 9 Feb 2022 14:53:51 +0100
From:   Christoph Hellwig <hch@lst.de>
To:     Jason Gunthorpe <jgg@ziepe.ca>
Cc:     Christoph Hellwig <hch@lst.de>,
        Dan Williams <dan.j.williams@intel.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Felix Kuehling <Felix.Kuehling@amd.com>,
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        "Pan, Xinhui" <Xinhui.Pan@amd.com>,
        Ben Skeggs <bskeggs@redhat.com>,
        Karol Herbst <kherbst@redhat.com>,
        Lyude Paul <lyude@redhat.com>,
        Alistair Popple <apopple@nvidia.com>,
        Logan Gunthorpe <logang@deltatee.com>,
        Ralph Campbell <rcampbell@nvidia.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
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        Maling list - DRI developers 
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Subject: Re: [PATCH 7/8] mm: remove the extra ZONE_DEVICE struct page
 refcount
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On Wed, Feb 09, 2022 at 08:29:56AM -0400, Jason Gunthorpe wrote:
> It is nice, but the other series are still impacted by the fsdax mess
> - they still stuff pages into ptes without proper refcounts and have
> to carry nonsense to dance around this problem.
> 
> I certainly would be unhappy if the amd driver, for instance, gained
> the fsdax problem as well and started pushing 4k pages into PMDs.

As said before: I think this all needs to be fixed.  But I'd rather
fix it gradually and I think this series is a nice step forward.
After that we can look at the pte mappings.