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Date:   Wed, 28 Sep 2022 16:52:02 +0800
From:   Chih-En Lin <shiyn.lin@gmail.com>
To:     John Hubbard <jhubbard@nvidia.com>
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Subject: Re: [RFC PATCH v2 9/9] mm: Introduce Copy-On-Write PTE table
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On Tue, Sep 27, 2022 at 02:26:19PM -0700, John Hubbard wrote:
> On 9/27/22 12:53, Chih-En Lin wrote:
> > I'm not familiar with THP right now. But we have a plan for looking
> > at it to see what will happen with COW PTE.
> > Currently, I can only say that I prefer to avoid involving the behavior
> > of huge-page/THP. If there are any ideas here please tell us.
> > 
> In order to be considered at all, this would have to at least behave 
> correctly in the presence of THP and hugetlbfs, IMHO. Those are no
> longer niche features.
> 

To make sure it will work well with them. During fork() and page fault,
we put the mechanism after the hug-page/THP to make it doesn't mess up.
It may have corner cases that I didn't handle. I will keep looking at
it.

Thanks,
Chih-En lin