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Date: Fri, 6 Apr 2018 00:03:10 -0700
From: Christoph Hellwig <hch@infradead.org>
Subject: Re: [PATCH] dax: adding fsync/msync support for device DAX
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To: Dan Williams <dan.j.williams@intel.com>
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On Thu, Apr 05, 2018 at 03:17:17PM -0700, Dan Williams wrote:
> > That means IFF ADR can fail like this we can't treat it as stable
> > storage and we must not support MAP_SYNC or equivalent device dax
> > behavior, period.
> 
> Makes sense, we won't pursue *sync() support on device-dax it doesn't fit.

We still have other bits of this way of thinking in the tree as far as
I can tell, e.g. the nvdimm_flush calls in pmem_make_request and thus
should come up with a coherent strategy if we trust ADR, and if we don't
fully trust it how to mitigate it.
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