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From:   Ming Lin <mlin@kernel.org>
Date:   Tue, 1 Jun 2021 18:06:26 -0700
Message-ID: <CAF1ivSZT_Ro2kw=VM7DfkAcNxWQwHNVc71g5JgbJeJH_XKAhVw@mail.gmail.com>
Subject: Re: [PATCH 2/2] mm: adds NOSIGBUS extension for out-of-band shmem read
To:     Linus Torvalds <torvalds@linux-foundation.org>
Cc:     Hugh Dickins <hughd@google.com>, Simon Ser <contact@emersion.fr>,
        Linux-MM <linux-mm@kvack.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
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On 6/1/2021 5:16 PM, Linus Torvalds wrote:
> This series passes my "looks fine, is simple and straightforward" test.
>
> One nit:
>
> On Tue, Jun 1, 2021 at 1:22 PM Ming Lin <mlin@kernel.org> wrote:
>>
>> +               error = vm_insert_page(vma, (unsigned long)vmf->address,
>> +                                       ZERO_PAGE(0));
>
> On architectures where this matters - bad virtual caches - it would be
> better to use ZERO_PAGE(vmf->address).
>
> It doesn't make a difference on any sane architecture, but it's the
> RightThing(tm) to do.


grep -Rn ZERO_PAGE linux/arch/ | grep define

s390 and mips do use the "address" of ZERO_PAGE(address)

Fixed.