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From:   Linus Torvalds <torvalds@linux-foundation.org>
Date:   Sun, 27 Dec 2020 17:54:32 -0800
Message-ID: <CAHk-=wiVrd4R2EVGCGtmybt6+u9LoGgMdnf12zc=sYL=QbvRWQ@mail.gmail.com>
Subject: Re: [PATCH 1/2] mm: Allow architectures to request 'old' entries when prefaulting
To:     "Kirill A. Shutemov" <kirill@shutemov.name>
Cc:     Hugh Dickins <hughd@google.com>,
        Matthew Wilcox <willy@infradead.org>,
        "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>,
        Will Deacon <will@kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Linux-MM <linux-mm@kvack.org>,
        Linux ARM <linux-arm-kernel@lists.infradead.org>,
        Catalin Marinas <catalin.marinas@arm.com>,
        Jan Kara <jack@suse.cz>, Minchan Kim <minchan@kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Vinayak Menon <vinmenon@codeaurora.org>,
        Android Kernel Team <kernel-team@android.com>
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On Sun, Dec 27, 2020 at 3:48 PM Kirill A. Shutemov <kirill@shutemov.name> wrote:
>
> I did what Hugh proposed and it got clear to my eyes. It gets somewhat
> large, but take a look.

Ok, it's not that much bigger, and the end result is certainly much
clearer wrt locking.

So that last version of yours with the fix for the uninitialized 'ret'
variable looks good to me.

Of course, I've said that before, and have been wrong. So ...

             Linus