From:   "Huang, Ying" <ying.huang@intel.com>
To:     Linus Torvalds <torvalds@linux-foundation.org>
Cc:     Andrew Morton <akpm@linux-foundation.org>, linux-mm@kvack.org,
        mm-commits@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [GIT PULL] hotfixes for 6.3-rc1
References: <20230304131528.4645d19a2ab897fb7518159e@linux-foundation.org>
        <CAHk-=wj9guryjifHyr26w73ta+kNeoHtGde682Z5N6OSjKu4UQ@mail.gmail.com>
        <20230304152058.de91bf7abf424383ce31d500@linux-foundation.org>
        <CAHk-=wiHX2NQiVH8uQZ_U8vB=qnzmQHauGAqAkC=4ZWp95ya8w@mail.gmail.com>
Date:   Mon, 06 Mar 2023 09:25:06 +0800
In-Reply-To: <CAHk-=wiHX2NQiVH8uQZ_U8vB=qnzmQHauGAqAkC=4ZWp95ya8w@mail.gmail.com>
        (Linus Torvalds's message of "Sat, 4 Mar 2023 15:37:11 -0800")
Message-ID: <87jzzu7jt9.fsf@yhuang6-desk2.ccr.corp.intel.com>
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Hi, Linus,

Linus Torvalds <torvalds@linux-foundation.org> writes:

> On Sat, Mar 4, 2023 at 3:21=E2=80=AFPM Andrew Morton <akpm@linux-foundati=
on.org> wrote:
>>
>> Ah. Ying did it this way:
>
> Yeah, I saw that patch flying past, but I actually think that it only
> silences the warning almost by mistake. There's nothing fundamental in
> there that a compiler wouldn't just follow across two assignments, and
> it just happens to now not trigger any more.
>
> Assigning to a union entry is a more fundamental operation in that
> respect. Not that the compiler still doesn't see that it's assigning a
> value that in the end is not really type compatible, so a different
> version of gcc could still warn, but at that point I feel like it's
> more of an actual compiler bug than just "oh, the compiler didn't
> happen to follow the cast through a temporary".

Yes.  Your fix is much better.  This can be used for
__page_set_anon_rmap() family too to make the code look better?

Best Regards,
Huang, Ying