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Bruce Fields" , Jeff Layton , Khalid Aziz , linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, Mike Kravetz Subject: Re: [PATCH RFC] mm: Add an fs-write seal to memfd Message-ID: <20181005211058.GA193964@joelaf.mtv.corp.google.com> References: <20181005192727.167933-1-joel@joelfernandes.org> <20181005125339.f6febfd3fcfdc69c6f408c50@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20181005125339.f6febfd3fcfdc69c6f408c50@linux-foundation.org> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Oct 05, 2018 at 12:53:39PM -0700, Andrew Morton wrote: > On Fri, 5 Oct 2018 12:27:27 -0700 "Joel Fernandes (Google)" 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. Sure, I will do that. thanks, - Joel