From owner-freebsd-geom@FreeBSD.ORG Thu Apr 26 22:37:16 2007 Return-Path: X-Original-To: freebsd-geom@freebsd.org Delivered-To: freebsd-geom@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id A2A4616A400; Thu, 26 Apr 2007 22:37:16 +0000 (UTC) (envelope-from jhb@freebsd.org) Received: from server.baldwin.cx (66-23-211-162.clients.speedfactory.net [66.23.211.162]) by mx1.freebsd.org (Postfix) with ESMTP id 3115B13C489; Thu, 26 Apr 2007 22:37:15 +0000 (UTC) (envelope-from jhb@freebsd.org) Received: from localhost.corp.yahoo.com (john@localhost [127.0.0.1]) (authenticated bits=0) by server.baldwin.cx (8.13.8/8.13.8) with ESMTP id l3QMbCWB078476; Thu, 26 Apr 2007 18:37:12 -0400 (EDT) (envelope-from jhb@freebsd.org) From: John Baldwin To: Scott Long Date: Thu, 26 Apr 2007 18:35:42 -0400 User-Agent: KMail/1.9.6 References: <52686.1177091835@critter.freebsd.dk> <200704261740.22987.jhb@freebsd.org> <463124A3.6070809@samsco.org> In-Reply-To: <463124A3.6070809@samsco.org> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200704261835.44220.jhb@freebsd.org> X-Greylist: Sender succeeded SMTP AUTH authentication, not delayed by milter-greylist-2.0.2 (server.baldwin.cx [127.0.0.1]); Thu, 26 Apr 2007 18:37:12 -0400 (EDT) X-Virus-Scanned: ClamAV 0.88.3/3165/Thu Apr 26 09:03:24 2007 on server.baldwin.cx X-Virus-Status: Clean X-Spam-Status: No, score=-4.4 required=4.2 tests=ALL_TRUSTED,BAYES_00 autolearn=ham version=3.1.3 X-Spam-Checker-Version: SpamAssassin 3.1.3 (2006-06-01) on server.baldwin.cx Cc: Maxim Sobolev , Poul-Henning Kamp , freebsd-current@freebsd.org, Ivan Voras , freebsd-geom@freebsd.org Subject: Re: GPT as default? X-BeenThere: freebsd-geom@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: GEOM-specific discussions and implementations List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 26 Apr 2007 22:37:16 -0000 On Thursday 26 April 2007 06:16:03 pm Scott Long wrote: > John Baldwin wrote: > > On Friday 20 April 2007 04:55:35 pm Maxim Sobolev wrote: > >> Scott Long wrote: > >>> Poul-Henning Kamp wrote: > >>>> In message , Ivan Voras writes: > >>>> > >>>>> Currently, the FreeBSD default is classic BSD partitions on top of > >>>>> MSDOS partitions, and there are a couple of inconvenient things about > >>>>> this arrangement: > >>>> The BSD partitioning should be discontinued as fast and firmly > >>>> as possible. By all means go GPT. > >>>> > >>> An i386/amd64 bootloader needs to be written that can understand GPT. > >>> My understanding is that the ia64 EFI/GPT loader has very few reusable > >>> bits. > >> It probably crazy idea, but I wonder if it's feasible to have > >> "mini-GEOM" layer in loader, so that it's possible to use existing GEOM > >> classes codebase there with little or no modifications. > > > > The loader is the easy part. boot1/2 is the hard one. :( You need both an > > EFI loader, and a non-EFI bootstrap to load a non-EFI loader that can grok > > GPT for the non-EFI case where we still want to use GPT. > > > > Are there real-world PC BIOS's that understand GPT but aren't EFI-based? GPT looks like an MBR for compat reasons, so probably any BIOS will see the AA55 at the end and boot it fine. However, the rest of the bootstrap has to know to ignore the fake MBR and read the real GPT. -- John Baldwin