From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752851Ab1GYUs0 (ORCPT ); Mon, 25 Jul 2011 16:48:26 -0400 Received: from terminus.zytor.com ([198.137.202.10]:40098 "EHLO mail.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751350Ab1GYUsY (ORCPT ); Mon, 25 Jul 2011 16:48:24 -0400 Message-ID: <4E2DD662.9060404@zytor.com> Date: Mon, 25 Jul 2011 13:47:30 -0700 From: "H. Peter Anvin" User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:5.0) Gecko/20110707 Thunderbird/5.0 MIME-Version: 1.0 To: Will Drewry CC: linux-kernel@vger.kernel.org, kay.sievers@vrfy.org, akpm@linux-foundation.org, Jens Axboe , Namhyung Kim , Trond Myklebust Subject: Re: [PATCH v3 1/2] init: add root=PARTUUID=UUID/PARTNROFF=%d support References: <1309468207-24199-1-git-send-email-wad@chromium.org> In-Reply-To: <1309468207-24199-1-git-send-email-wad@chromium.org> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 06/30/2011 02:10 PM, Will Drewry wrote: > Expand root=PARTUUID=UUID syntax to support selecting a root partition > by integer offset from a known, unique partition. This approach > provides similar properties to specifying a device and partition number, > but using the UUID as the unique path prior to evaluating the offset. > > For example, > root=PARTUUID=99DE9194-FC15-4223-9192-FC243948F88B/PARTNROFF=1 > selects the partition with UUID 99DE.. then select the next > partition. > > This change is motivated by a particular usecase in Chromium OS where > the bootloader can easily determine what partition it is on (by UUID) > but doesn't perform general partition table walking. > > That said, support for this model provides a direct mechanism for the > user to modify the root partition to boot without specifically needing > to extract each UUID or update the bootloader explicitly when the root > partition UUID is changed (if it is recreated to be larger, for > instance). Pinning to a /boot-style partition UUID allows the arbitrary > root partition reconfiguration/modifications with slightly less > ambiguity than just [dev][partition] and less stringency than the > specific root partition UUID. > Obklibcsnark: Does anyone still doubt that as long as this kind of code exists in the kernel that it will not get continually added to? -hpa