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Date:   Fri, 5 Oct 2018 12:53:39 -0700
From:   Andrew Morton <akpm@linux-foundation.org>
To:     "Joel Fernandes (Google)" <joel@joelfernandes.org>
Cc:     linux-kernel@vger.kernel.org, kernel-team@android.com,
        jreck@google.com, john.stultz@linaro.org, tkjos@google.com,
        gregkh@linuxfoundation.org, Al Viro <viro@zeniv.linux.org.uk>,
        "J. Bruce Fields" <bfields@fieldses.org>,
        Jeff Layton <jlayton@kernel.org>,
        Khalid Aziz <khalid.aziz@oracle.com>,
        linux-fsdevel@vger.kernel.org, linux-mm@kvack.org,
        Mike Kravetz <mike.kravetz@oracle.com>
Subject: Re: [PATCH RFC] mm: Add an fs-write seal to memfd
Message-Id: <20181005125339.f6febfd3fcfdc69c6f408c50@linux-foundation.org>
In-Reply-To: <20181005192727.167933-1-joel@joelfernandes.org>
References: <20181005192727.167933-1-joel@joelfernandes.org>
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On Fri,  5 Oct 2018 12:27:27 -0700 "Joel Fernandes (Google)" <joel@joelfernandes.org> wrote:

> To support the usecase, this patch adds a new F_SEAL_FS_WRITE seal which
> prevents any future mmap and write syscalls from succeeding while
> keeping the existing mmap active. The following program shows the seal
> working in action:

Please be prepared to create a manpage patch for this one.