From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261692AbVBHXgK (ORCPT ); Tue, 8 Feb 2005 18:36:10 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261693AbVBHXgK (ORCPT ); Tue, 8 Feb 2005 18:36:10 -0500 Received: from hera.kernel.org ([209.128.68.125]:30898 "EHLO hera.kernel.org") by vger.kernel.org with ESMTP id S261692AbVBHXfD (ORCPT ); Tue, 8 Feb 2005 18:35:03 -0500 To: linux-kernel@vger.kernel.org From: hpa@zytor.com (H. Peter Anvin) Subject: Re: 3TB disk hassles Date: Tue, 8 Feb 2005 23:33:51 +0000 (UTC) Organization: Mostly alphabetical, except Q, which We do not fancy Message-ID: References: <20050206105958.42872.qmail@web26501.mail.ukl.yahoo.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7BIT X-Trace: terminus.zytor.com 1107905631 3793 127.0.0.1 (8 Feb 2005 23:33:51 GMT) X-Complaints-To: news@terminus.zytor.com NNTP-Posting-Date: Tue, 8 Feb 2005 23:33:51 +0000 (UTC) X-Newsreader: trn 4.0-test76 (Apr 2, 2001) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Followup to: <20050206105958.42872.qmail@web26501.mail.ukl.yahoo.com> By author: Neil Conway In newsgroup: linux.dev.kernel > > Since writing the above, I've been searching for more info. I > downloaded four different versions of grub (GNU Grub Legacy, GNU Grub2, > gentoo and Fedora Core 3). NONE of these showed any evidence of GPT > support (I was in a hurry, so I searched for strings EFI, GUID, GPT, > TB). > > Mucho confused puppy here. > > I fail to see how grub can work on a GPT boot device if it can't parse > the partition table. I conclude that I'm still missing something. > Perhaps a layer before grub is supposed to parse the GPT instead? If > so, isn't that getting us straight back to a GPT-aware BIOS? > > Tell me if this logic is broken: even if a special boot sector is used, > which IS GPT-aware (though fitting that into the boot sector would be a > challenge ;-)), once grub loads, it's still going to have to figure out > how to find the root(hdX,Y) partition from which to load the kernel > image. This surely means it has to have either a GPT-parser > internally, or rely on a pre-parsed list. No? > > Perhaps one of the other several distros (that I didn't check) has a > GPT-aware grub. But Tomas Carnecky said early in this thread that > gentoo had allowed him to set up a GPT-booting system on x86. I guess > it's possible that a cheat was used - maybe an old-style partition > table in the MBR was used to define the first (boot) partition, but > surely that's forbidden by the whole EFI spec anyway? > No, it's encouraged. > > Andries Brouwer kindly wrote a patch which I haven't had time to test > yet (see earlier in thread). While it would be nice to find a way > around the problem which didn't require deviations from vanilla > distros, I think Andries' patch is looking like the only sane fix right > now. > Note that Andries' patch does *EXACTLY* the same thing as the GPT/EFI spec does (by using an old-style partition table for the first 2 TB.) It should be pretty easy to add native support for this in EXTLINUX; the big problem is supporting true access > 2 TB, which I currently don't have any way to test. I'll put that on my todo list. -hpa