Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754353AbYKPDsg (ORCPT ); Sat, 15 Nov 2008 22:48:36 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751951AbYKPDs1 (ORCPT ); Sat, 15 Nov 2008 22:48:27 -0500 Received: from casper.infradead.org ([85.118.1.10]:35805 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751652AbYKPDs0 (ORCPT ); Sat, 15 Nov 2008 22:48:26 -0500 Date: Sat, 15 Nov 2008 19:49:14 -0800 From: Arjan van de Ven To: Bernhard Walle Cc: x86@kernel.org, linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, Bernhard Walle Subject: Re: [PATCH 2/2] Add dev.mem.restricted sysctl Message-ID: <20081115194914.6791b96c@infradead.org> In-Reply-To: <1226793823-32360-3-git-send-email-bwalle@suse.de> References: <1226793823-32360-1-git-send-email-bwalle@suse.de> <1226793823-32360-3-git-send-email-bwalle@suse.de> Organization: Intel X-Mailer: Claws Mail 3.6.0 (GTK+ 2.14.4; i386-redhat-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-SRS-Rewrite: SMTP reverse-path rewritten from by casper.infradead.org See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1133 Lines: 30 On Sun, 16 Nov 2008 01:03:43 +0100 Bernhard Walle wrote: > When CONFIG_STRICT_DEVMEM is set, live debugging is not possible with > the crash utility (see http://people.redhat.com/~anderson). For > distributors who ship a generic kernel it's difficult: Disabling > CONFIG_STRICT_DEVMEM is possible, but in general the protection > provided by CONFIG_STRICT_DEVMEM is useful. However, live debugging > should be still neceessary. > > This patch now adds a dev.mem.restricted sysctl that defaults to 0 > (off). When set to 1 (on), /dev/mem access is unrestricted and crash > can be used. > sounds like a really bad idea to me. If you want to use /dev/mem like this, don't enable the config option to restrict it. Really. -- Arjan van de Ven Intel Open Source Technology Centre For development, discussion and tips for power savings, visit http://www.lesswatts.org -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/