From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754709AbbIRPAW (ORCPT ); Fri, 18 Sep 2015 11:00:22 -0400 Received: from mail.cmpwn.com ([45.56.77.53]:37497 "EHLO mail.cmpwn.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753068AbbIRPAT (ORCPT ); Fri, 18 Sep 2015 11:00:19 -0400 Subject: Re: Failover root devices To: =?UTF-8?Q?Ortwin_Gl=c3=bcck?= , Richard Weinberger References: <55FAA6BB.3060008@odi.ch> <20150917114955.GA2600@homura> <55FAFD1D.8030305@cmpwn.com> <55FAFDE1.2020707@nod.at> <55FB00E6.3090801@cmpwn.com> <55FB03B8.2000101@nod.at> <55FB03E8.3000604@cmpwn.com> <55FB0441.6040709@nod.at> <55FB0498.9060301@cmpwn.com> <55FB0531.3050006@nod.at> <55FB0646.1020704@cmpwn.com> <55FC26B5.7080308@odi.ch> Cc: "linux-kernel@vger.kernel.org" From: Drew DeVault Message-ID: <55FC2701.8070300@cmpwn.com> Date: Fri, 18 Sep 2015 11:00:17 -0400 MIME-Version: 1.0 In-Reply-To: <55FC26B5.7080308@odi.ch> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > I personally think this is opening a can of worms. Now it's just a list > of alternative root devices. But the kernel knows absolutely nothing > about these. When is it fine to try an alternative? Why did the first > one not work? Did we just not wait long enough? Or is it a failed RAID > device? Or is it an encrypted disk that needs setup? Or is it on NFS and > the network is not available (or we are lacking driver firmware)? I don't think these are problems that aren't already inherent in a single root device via root=. > It could actually introduce security problems: if I know that a device > will fallback to an alternative root (under my control), I can try and > DOS the primary root. If you have physical access then the machine is yours to do with as you please. -- Drew DeVault