From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753283Ab1KSJbh (ORCPT ); Sat, 19 Nov 2011 04:31:37 -0500 Received: from mail-ww0-f44.google.com ([74.125.82.44]:55423 "EHLO mail-ww0-f44.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752518Ab1KSJbf (ORCPT ); Sat, 19 Nov 2011 04:31:35 -0500 Message-ID: <4EC77605.5090605@gmail.com> Date: Sat, 19 Nov 2011 10:25:25 +0100 From: Marco Stornelli User-Agent: Mozilla/5.0 (X11; U; Linux i686; it; rv:1.9.2.23) Gecko/20110920 SUSE/3.1.15 Thunderbird/3.1.15 MIME-Version: 1.0 To: Kees Cook CC: linux-kernel@vger.kernel.org, Chen Gong , Greg Kroah-Hartman , Andrew Morton , Arnd Bergmann , Nicolas Pitre , Paul Gortmaker Subject: Re: [PATCH 2/2] ramoops: remove module parameters References: <1321644698-13677-1-git-send-email-keescook@chromium.org> <1321644698-13677-3-git-send-email-keescook@chromium.org> In-Reply-To: <1321644698-13677-3-git-send-email-keescook@chromium.org> Content-Type: text/plain; charset=ISO-8859-15; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Il 18/11/2011 20:31, Kees Cook ha scritto: > The ramoops driver is intended to be used with platforms that define > persistent memory regions. If memory regions were configurable with > module parameters, it would be possible to read some RAM regions via > the pstore interface without access to /dev/mem (which would result > in a loss of kernel memory privacy when a system is built with > STRICT_DEVMEM), so remove this ability completely. > I don't like it very much. The loss of module parameters give us less flexibility. The main goal of this driver is debug, so I think it should be fast to use. I mean it's not more possible reserve a memory region and load the module "on-the-fly", it needs a platform device, it's ok but I think it's a little bit more complicated, (without talking about platforms without a device tree source). I don't understand the problem of strict devmem. We shouldn't use kernel memory region but only reserved ones and the driver doesn't use the request_mem_region_exclusive, am I wrong? Marco