From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752317AbaLGPlw (ORCPT ); Sun, 7 Dec 2014 10:41:52 -0500 Received: from mail-wg0-f53.google.com ([74.125.82.53]:62825 "EHLO mail-wg0-f53.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751061AbaLGPlt (ORCPT ); Sun, 7 Dec 2014 10:41:49 -0500 From: robert.ward114@googlemail.com To: arnd@arndb.de, gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org Cc: Rob Ward Subject: [PATCH 0/3] /dev/mem as optional device + associated tidy up Date: Sun, 7 Dec 2014 15:40:32 +0000 Message-Id: <1417966835-14012-1-git-send-email-robert.ward114@googlemail.com> X-Mailer: git-send-email 2.2.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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. Rob Ward (3): drivers: char: mem: Make /dev/mem an optional device drivers: char: mem: Simplify DEVKMEM configuration drivers: char: mem: Simplify DEVPORT configuration drivers/char/Kconfig | 9 +++++++++ drivers/char/mem.c | 18 +++++------------- 2 files changed, 14 insertions(+), 13 deletions(-) -- 2.0.2