From owner-freebsd-net Thu Aug 9 11:12:41 2001 Delivered-To: freebsd-net@freebsd.org Received: from mail.wrs.com (unknown-1-11.windriver.com [147.11.1.11]) by hub.freebsd.org (Postfix) with ESMTP id A301837B401; Thu, 9 Aug 2001 11:12:32 -0700 (PDT) (envelope-from jhb@FreeBSD.org) Received: from laptop.baldwin.cx (john@[147.11.46.201]) by mail.wrs.com (8.9.3/8.9.1) with ESMTP id LAA29433; Thu, 9 Aug 2001 11:12:30 -0700 (PDT) Message-ID: X-Mailer: XFMail 1.4.0 on FreeBSD X-Priority: 3 (Normal) Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 8bit MIME-Version: 1.0 In-Reply-To: Date: Thu, 09 Aug 2001 11:12:32 -0700 (PDT) From: John Baldwin To: Mark Peek Subject: Re: Problem with pxeboot and binutils-2.11 Cc: current@FreeBSD.org, net@FreeBSD.org, Harti Brandt Sender: owner-freebsd-net@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.org On 09-Aug-01 Mark Peek wrote: > At 4:46 PM +0200 8/9/01, Harti Brandt wrote: >>some time ago we reported a problem with pxeboot under -current (see below). >>We have tried to track down the problem and it seems to be a bug or a >>feature in gas or libbfd. It turns out, that the output from pxeldr before >>the binutils-2.11 import on 5/29/2001 was 500 bytes long. After the import >>the output has grown to 512 byte. The excess bytes contain a jump to the >>address 512 and a number of NOPs. The result of this is, that the loader >>image which is located imediately after pxeldr is shifted by 12 bytes >>and the address calculations in pxeldr.s are wrong now. >> >>Unfortunately we're not able to find out what new bug^h^h^hfeature of >>gas or libbfd causes this behaviour. A simple workaround is to strip the >>excess bytes from pxeldr just before building pxeboot, but that is REALLY >>ugly: > > > It appears that gas is now properly padding the end of the text > section (and inserting the jmp and nops). This, in turn, misaligns > the loader that is tacked onto the end of the pxeldr. I'm currently > not setup to test pxeboot'ing but here's a patch that might fix it. The disassembly looks right, I just don't have a means for testing it. -- John Baldwin -- http://www.FreeBSD.org/~jhb/ PGP Key: http://www.baldwin.cx/~john/pgpkey.asc "Power Users Use the Power to Serve!" - http://www.FreeBSD.org/ To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-net" in the body of the message