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From:   Jann Horn <jannh@google.com>
Date:   Wed, 30 Sep 2020 03:35:14 +0200
Message-ID: <CAG48ez1b7_tSyFndMOefGECog4Dde5XmRHCtWen9=CdJkho+HA@mail.gmail.com>
Subject: Re: [PATCH 1/4] mm/gup_benchmark: Take the mmap lock around GUP
To:     Andrew Morton <akpm@linux-foundation.org>,
        Linux-MM <linux-mm@kvack.org>
Cc:     kernel list <linux-kernel@vger.kernel.org>,
        "Eric W . Biederman" <ebiederm@xmission.com>,
        Michel Lespinasse <walken@google.com>,
        Mauro Carvalho Chehab <mchehab@kernel.org>,
        Sakari Ailus <sakari.ailus@linux.intel.com>
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On Wed, Sep 30, 2020 at 3:19 AM Jann Horn <jannh@google.com> wrote:
> To be safe against concurrent changes to the VMA tree, we must take the
> mmap lock around GUP operations (excluding the GUP-fast family of
> operations, which will take the mmap lock by themselves if necessary).

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