From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753523AbaLGTfi (ORCPT ); Sun, 7 Dec 2014 14:35:38 -0500 Received: from mout.kundenserver.de ([212.227.126.130]:53743 "EHLO mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752223AbaLGTff (ORCPT ); Sun, 7 Dec 2014 14:35:35 -0500 From: Arnd Bergmann To: robert.ward114@googlemail.com Cc: gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 0/3] /dev/mem as optional device + associated tidy up Date: Sun, 07 Dec 2014 20:35:31 +0100 Message-ID: <8719187.RB9WVc9E5S@wuerfel> User-Agent: KMail/4.11.5 (Linux/3.16.0-10-generic; KDE/4.11.5; x86_64; ; ) In-Reply-To: <1417966835-14012-1-git-send-email-robert.ward114@googlemail.com> References: <1417966835-14012-1-git-send-email-robert.ward114@googlemail.com> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" X-Provags-ID: V03:K0:icxB9ZoNKNw2j6f4G3TU8jTUNd+dYpex2bpChV7qlCbqEgBAJf7 jIgsO1I/5Ho7wiqzoF7leaHgibSv4Q6nf0EiLCop+yZd9zSDKMcOywky1S39nFoHPMr+vST yzWIKy8j/WK9ofOsD6emUCw2CzQnjMn5PuhB7+nzZATsl1I+rUQe98d+mFK7h/QKt9hOxxX /S4OzsjSg1uCfeGeLZgDw== X-UI-Out-Filterresults: notjunk:1; Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sunday 07 December 2014 15:40:32 robert.ward114@googlemail.com wrote: > From: Rob Ward > > Makes the /dev/mem device optional using the CONFIG_DEVMEM option. > > This brings /dev/mem in line with /dev/kmem so it can de disabled. > Disabling /dev/mem is preferable on devices that do not require > direct access to memory in order to improve security. This is especially > true on platforms where no restiction is placed on the areas of memory > that can be accessed(for example mips) without custom modifcations to > the kernel source. > > The implementation of this functionality declares the mem_fops structure > as __maybe_unused to eliminate the need for #ifdefs throughout the > file. > > Follow up changes are present to change CONFIG_DEVKMEM and CONFIG_DEVPORT > to use __maybe_unused. This simplifies the code and make the > implementations consistent. > Acked-by: Arnd Bergmann