From owner-freebsd-current@FreeBSD.ORG Fri Apr 20 17:15:24 2007 Return-Path: X-Original-To: freebsd-current@freebsd.org Delivered-To: freebsd-current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id 4949216A407; Fri, 20 Apr 2007 17:15:24 +0000 (UTC) (envelope-from des@des.no) Received: from tim.des.no (tim.des.no [194.63.250.121]) by mx1.freebsd.org (Postfix) with ESMTP id 069CA13C43E; Fri, 20 Apr 2007 17:15:23 +0000 (UTC) (envelope-from des@des.no) Received: from tim.des.no (localhost [127.0.0.1]) by spam.des.no (Postfix) with ESMTP id C1BE4207E; Fri, 20 Apr 2007 19:15:19 +0200 (CEST) X-Spam-Tests: AWL X-Spam-Learn: disabled X-Spam-Score: 0.0/3.0 X-Spam-Checker-Version: SpamAssassin 3.1.7 (2006-10-05) on tim.des.no Received: from dwp.des.no (des.no [80.203.243.180]) by smtp.des.no (Postfix) with ESMTP id AF36C2049; Fri, 20 Apr 2007 19:15:19 +0200 (CEST) Received: by dwp.des.no (Postfix, from userid 1001) id 8133E542C; Fri, 20 Apr 2007 19:15:17 +0200 (CEST) From: des@des.no (Dag-Erling =?iso-8859-1?Q?Sm=F8rgrav?=) To: Ivan Voras References: Date: Fri, 20 Apr 2007 19:15:17 +0200 In-Reply-To: (Ivan Voras's message of "Fri, 20 Apr 2007 17:27:13 +0200") Message-ID: <86wt076k7u.fsf@dwp.des.no> User-Agent: Gnus/5.110006 (No Gnus v0.6) Emacs/21.3 (berkeley-unix) MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable Cc: freebsd-current@freebsd.org, freebsd-geom@freebsd.org Subject: Re: GPT as default? X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 20 Apr 2007 17:15:24 -0000 Ivan Voras writes: > Many systems (including MacOS X and Solaris) are moving to GPT > partitions (http://en.wikipedia.org/wiki/GUID_Partition_Table), mostly > because they don't have the above limitations. My proposal is that we > deprecate BSD labels and move to GPT in 7.0 (or more correctly, if the > stars were to be benevolent on us, on the new systems that are > installed by the new GPT-aware installer :) ). Not unless geom_gpt receives considerable attention. Currently, it is not even possible to list the GPT, let alone create new partitions, if one of the partitions is open. GPT can not be the default partitioning scheme until this is addressed. > The second is more serious: FreeBSD boot code cannot boot from a GPT > partition. > > Part of the problem is that GPT uses GUIDs for distinguishing > partition types, so the current code that recognizes various partition > types (Linux, FreeBSD, NTFS - the famous "F1" prompt) may need to be > thrown out since each GUID is 16 bytes long and AFAIK there's only > about 300 bytes in the MBR for the boot code. DOS partitions normally start on a cylinder boundary, even though cylinders no longer mean anything. This means there is plenty of space for code and data between the MBR and the first partition. I don't know if this is also the case with GPT. > Now, the problem is - is someone with enough assembler knowledge > interested in implementing a GPT-aware boot loader? :) Capable, yes. Interested, perhaps. DES --=20 Dag-Erling Sm=F8rgrav - des@des.no