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Date: Fri, 2 Feb 2024 13:57:35 +0100
From: Michal Hocko <mhocko@suse.com>
To: Lance Yang <ioworker0@gmail.com>
Cc: akpm@linux-foundation.org, zokeefe@google.com, david@redhat.com,
	songmuchun@bytedance.com, shy828301@gmail.com, peterx@redhat.com,
	minchan@kernel.org, linux-mm@kvack.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH 1/1] mm/khugepaged: skip copying lazyfree pages on
 collapse
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On Fri 02-02-24 20:52:48, Lance Yang wrote:
> On Fri, Feb 2, 2024 at 8:27 PM Michal Hocko <mhocko@suse.com> wrote:
> >
> > On Fri 02-02-24 19:18:31, Lance Yang wrote:
> > > IMO, since it's treated the same as pte_none,
> > > perhaps lazyfree pages shouldn't be copied to
> > > the new huge page.
> >
> > Why? The content of MADV_FREE page is valid until it is reclaimed.
> 
> IMO, if MADV_FREE pages are considered valid until
> reclaimed, treating them the same as pte_none might
> pose a conflict.

What kind of conflict?
-- 
Michal Hocko
SUSE Labs