From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pl1-f198.google.com (mail-pl1-f198.google.com [209.85.214.198]) by kanga.kvack.org (Postfix) with ESMTP id 6E76B6B0010 for ; Fri, 5 Oct 2018 15:53:54 -0400 (EDT) Received: by mail-pl1-f198.google.com with SMTP id e3-v6so12125468pld.13 for ; Fri, 05 Oct 2018 12:53:54 -0700 (PDT) Received: from mail.linuxfoundation.org (mail.linuxfoundation.org. [140.211.169.12]) by mx.google.com with ESMTPS id d31-v6si4997557pld.301.2018.10.05.12.53.53 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 05 Oct 2018 12:53:53 -0700 (PDT) Date: Fri, 5 Oct 2018 12:53:39 -0700 From: Andrew Morton 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> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: "Joel Fernandes (Google)" 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 , "J. Bruce Fields" , Jeff Layton , Khalid Aziz , linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, Mike Kravetz 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.