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From: Lance Yang <ioworker0@gmail.com>
Date: Fri, 2 Feb 2024 20:52:48 +0800
Message-ID: <CAK1f24mvBkc2c=fHL6UxMhL2mgLHVrSwZfE5516bOR0yVdfZpQ@mail.gmail.com>
Subject: Re: [PATCH 1/1] mm/khugepaged: skip copying lazyfree pages on collapse
To: Michal Hocko <mhocko@suse.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
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On Fri, Feb 2, 2024 at 8:27=E2=80=AFPM 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.

Thanks,
Lance

> --
> Michal Hocko
> SUSE Labs