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From:   Linus Torvalds <torvalds@linux-foundation.org>
Date:   Sun, 25 Jun 2023 12:42:25 -0700
Message-ID: <CAHk-=wj8b6joppjpYW=pi2r2LJgKHQKDwB9NkDmbsQAzWgf4AA@mail.gmail.com>
Subject: Re: [PATCH] mm/khugepaged: fix regression in collapse_file()
To:     Hugh Dickins <hughd@google.com>
Cc:     David Stevens <stevensd@chromium.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Peter Xu <peterx@redhat.com>,
        Matthew Wilcox <willy@infradead.org>,
        "Kirill A . Shutemov" <kirill@shutemov.name>,
        Yang Shi <shy828301@gmail.com>,
        David Hildenbrand <david@redhat.com>,
        Jiaqi Yan <jiaqiyan@google.com>, linux-kernel@vger.kernel.org,
        linux-mm@kvack.org
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On Sun, 25 Jun 2023 at 12:06, Hugh Dickins <hughd@google.com> wrote:
>
> Linus, I'm rushing this directly to you, but not really expecting you
> to put it in at this stage, unless you're very comfortable with it,
> or perhaps it catches Matthew's eye and gets a quick Ack from him.

Yeah, the fix and explanation sound fine to me, but the maple tree
code confuses me enough and has been subtle enough (as exemplified by
this bug and many others) that there's no way I'll apply this just
before the final 6.4 without some "Ack, that's obviously correct" from
Willy or Liam or somebody.

Willy?

                    Linus