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From:   Qian Cai <cai@lca.pw>
Mime-Version: 1.0 (1.0)
Subject: Re: [PATCH] mm/page_counter: fix various data races
Date:   Wed, 29 Jan 2020 07:25:39 -0500
Message-Id: <2D795DB7-66FE-4F01-872F-F8ACAE9505EF@lca.pw>
References: <59f892d0-5fc4-ae32-ce65-5a688d9180c8@I-love.SAKURA.ne.jp>
Cc:     Dmitry Vyukov <dvyukov@google.com>,
        Michal Hocko <mhocko@kernel.org>, akpm@linux-foundation.org,
        hannes@cmpxchg.org, elver@google.com, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org
In-Reply-To: <59f892d0-5fc4-ae32-ce65-5a688d9180c8@I-love.SAKURA.ne.jp>
To:     Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk


> On Jan 29, 2020, at 7:13 AM, Tetsuo Handa <penguin-kernel@i-love.sakura.ne=
.jp> wrote:
>=20
> By the way, can READ_ONCE()/WRITE_ONCE() really solve this warning?
> The link above says read/write on the same location ( mm/page_counter.c:12=
9 ).
> I don't know how READ_ONCE()/WRITE_ONCE() can solve the race.

That looks like a different one where it complains about c->failcnt++. I=E2=80=
=99ll send a separate patch for that.=