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Date:   Wed, 20 Mar 2019 01:01:06 +0000
From:   Christopher Lameter <cl@linux.com>
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To:     Dave Chinner <david@fromorbit.com>
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Subject: Re: [PATCH v4 1/1] mm: introduce put_user_page*(), placeholder
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On Wed, 20 Mar 2019, Dave Chinner wrote:

> So the plan for GUP vs writeback so far is "break fsync()"? :)

Well if its an anonymous page and not a file backed page then the
semantics are preserved. Disallow GUP long term pinning (marking stuff like in this
patchset may make that possible) and its clean.