From owner-freebsd-stable@FreeBSD.ORG Fri Feb 17 21:50:10 2012 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id E5754106566C; Fri, 17 Feb 2012 21:50:10 +0000 (UTC) (envelope-from fjwcash@gmail.com) Received: from mail-pz0-f54.google.com (mail-pz0-f54.google.com [209.85.210.54]) by mx1.freebsd.org (Postfix) with ESMTP id AC30C8FC08; Fri, 17 Feb 2012 21:50:10 +0000 (UTC) Received: by daec6 with SMTP id c6so4181046dae.13 for ; Fri, 17 Feb 2012 13:50:10 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; bh=QNGZf7kKO+bVyr+a6Lt4lLIJFi6TMGUKIWCSD9qawK4=; b=tJqGv5Q9+Yt8v7AJqh0pGlQv6o1LHAcn9qzNhmBGV7hlNRhN2LbGqNLDX+/IY04PZe XykkPiXeG5Ij37t0e/TEB9+c0CLw00q2y1fY4KxBhjAX6dLpIIddPXlqpOI4fbSnjQUy d6M1o/5yev9d0F/Vmdw/3Pb9GNCR9lcGx8u/4= MIME-Version: 1.0 Received: by 10.68.74.74 with SMTP id r10mr28667052pbv.83.1329515410298; Fri, 17 Feb 2012 13:50:10 -0800 (PST) Received: by 10.68.193.132 with HTTP; Fri, 17 Feb 2012 13:50:08 -0800 (PST) In-Reply-To: <4F3EC8DD.6040500@FreeBSD.org> References: <20120217.160430.406937514120319292.hrs@allbsd.org> <4F3E3000.9000206@FreeBSD.org> <20120217.232843.2212672671663755444.hrs@allbsd.org> <4F3EC8DD.6040500@FreeBSD.org> Date: Fri, 17 Feb 2012 13:50:08 -0800 Message-ID: From: Freddie Cash To: Andriy Gapon Content-Type: text/plain; charset=UTF-8 Cc: wblock@wonkity.com, freebsd-stable@freebsd.org, 000.fbsd@quip.cz, mandrews@bit0.com, freebsd@jdc.parodius.com Subject: Re: New BSD Installer X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 17 Feb 2012 21:50:11 -0000 On Fri, Feb 17, 2012 at 1:38 PM, Andriy Gapon wrote: > And just in case: > Unified Extensible Firmware Interface Specification Version 2.3.1, Errata A > September 7, 2011 says: > [snip] >> Two GPT Header structures are stored on the device: the primary and the >> backup. The primary GPT Header must be located in LBA 1 (i.e., the second >> logical block), and the backup GPT Header must be located in the last LBA >> of the device. > > I can not see any ambiguity or openness to interpretation in this paragraph. Unless it's specified somewhere else (which is possible), in this paragraph, "device" does not necessarily mean "physical disk". "Last LBA of the device" could be interpreted as "last LBA of the GEOM provider". The beauty of GEOM is that "device" is whatever logical mapping it provides. After all, LBAs are logical addresses (it's right there in the name!), not hardwired physical sector addresses. ;) If they were hardwired, then how would internal sector remapping work? ;) -- Freddie Cash fjwcash@gmail.com