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Date: Wed, 9 Feb 2022 07:23:45 +0100
From: Christoph Hellwig <hch@lst.de>
To: Dan Williams <dan.j.williams@intel.com>
Cc: Christoph Hellwig <hch@lst.de>,
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Subject: Re: [PATCH 7/8] mm: remove the extra ZONE_DEVICE struct page
 refcount
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References: <20220207063249.1833066-1-hch@lst.de> <20220207063249.1833066-8-hch@lst.de> <CAPcyv4h_axDTmkZ35KFfCdzMoOp8V3dc6btYGq6gCj1OmLXM=g@mail.gmail.com>
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On Tue, Feb 08, 2022 at 07:30:11PM -0800, Dan Williams wrote:
> Interesting. I had expected that to really fix the refcount problem
> that fs/dax.c would need to start taking real page references as pages
> were added to a mapping, just like page cache.

I think we should do that eventually.  But I think this series that
just attacks the device private type and extends to the device coherent
and p2p enhacements is a good first step to stop the proliferation of
the one off refcount and to allow to deal with the fsdax pages in another
more focuessed series.