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Date: Thu, 6 Aug 2015 15:45:31 -0500 (CDT)
From: Christoph Lameter <cl@linux.com>
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To: Hugh Dickins <hughd@google.com>
cc: "Kirill A. Shutemov" <kirill@shutemov.name>,
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Subject: Re: page-flags behavior on compound pages: a worry
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On Thu, 6 Aug 2015, Hugh Dickins wrote:

> > I know a patchset which solves this! ;)
>
> Oh, and I know a patchset which avoids these problems completely,
> by not using compound pages at all ;)

Another dumb idea: Stop the insanity of splitting pages on the fly?
Splitting pages should work like page migration: Lock everything down and
ensure no one is using the page and then do it. That way the compound pages
and its metadata are as stable as a regular page.