From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with archive (Exim 4.43) id 1MIr86-0006P4-Ed for mharc-grub-devel@gnu.org; Mon, 22 Jun 2009 17:32:42 -0400 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1MIr83-0006Ko-RQ for grub-devel@gnu.org; Mon, 22 Jun 2009 17:32:39 -0400 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1MIr7z-0006Jn-Id for grub-devel@gnu.org; Mon, 22 Jun 2009 17:32:39 -0400 Received: from [199.232.76.173] (port=57695 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1MIr7z-0006Jk-FH for grub-devel@gnu.org; Mon, 22 Jun 2009 17:32:35 -0400 Received: from aybabtu.com ([69.60.117.155]:47341) by monty-python.gnu.org with esmtps (TLS-1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.60) (envelope-from ) id 1MIr7z-00007V-37 for grub-devel@gnu.org; Mon, 22 Jun 2009 17:32:35 -0400 Received: from [192.168.10.10] (helo=thorin) by aybabtu.com with esmtp (Exim 4.69) (envelope-from ) id 1MIq4x-0000SY-Uh for grub-devel@gnu.org; Mon, 22 Jun 2009 22:25:24 +0200 Received: from rmh by thorin with local (Exim 4.69) (envelope-from ) id 1MIr7w-00031I-76 for grub-devel@gnu.org; Mon, 22 Jun 2009 23:32:32 +0200 Date: Mon, 22 Jun 2009 23:32:32 +0200 From: Robert Millan To: The development of GRUB 2 Message-ID: <20090622213232.GB10027@thorin> References: <20090621181748.GA21152@thorin> <20090621225332.GB2360@thorin> <1245633761.9864.34.camel@mj> <20090622095252.GC8969@thorin> <1245699543.2561.1.camel@mj> <20090622205213.GB7871@thorin> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20090622205213.GB7871@thorin> Organization: free as in freedom X-Message-Flag: Worried about Outlook viruses? Switch to Thunderbird! www.mozilla.com/thunderbird X-Debbugs-No-Ack: true User-Agent: Mutt/1.5.18 (2008-05-17) X-detected-operating-system: by monty-python.gnu.org: GNU/Linux 2.6 (newer, 1) Subject: Re: [PATCH] access gdtdesc on segment 0 unconditionally (Re: [PATCH] i386-qemu port) X-BeenThere: grub-devel@gnu.org X-Mailman-Version: 2.1.5 Precedence: list Reply-To: The development of GRUB 2 List-Id: The development of GRUB 2 List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 22 Jun 2009 21:32:40 -0000 On Mon, Jun 22, 2009 at 10:52:13PM +0200, Robert Millan wrote: > I don't think it's possible to use relative addresses > with this particular instruction. Uhm sorry, this was silly. Of course you can use addresses relative to a segment in lgdt, but this doesn't change the fact that GAS always gives you absolute ones. Also, I'm not sure if it's possible to use a 16-bit field in this instruction, it could be that the field is always 32-bit, even if it's relative to a segment. This dump is from the i386-pc kernel.img: 836f: 2e 67 66 0f 01 15 68 addr32 lgdtl %cs:0x8368 8376: 83 00 00 a little-endian 0x00008368 is seen here, indicating the field is 32-bit. -- Robert Millan The DRM opt-in fallacy: "Your data belongs to us. We will decide when (and how) you may access your data; but nobody's threatening your freedom: we still allow you to remove your data and not access it at all."