From owner-freebsd-current@FreeBSD.ORG Wed Jan 5 01:36:07 2005 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 48A3216A4CE for ; Wed, 5 Jan 2005 01:36:07 +0000 (GMT) Received: from wproxy.gmail.com (wproxy.gmail.com [64.233.184.205]) by mx1.FreeBSD.org (Postfix) with ESMTP id E515843D45 for ; Wed, 5 Jan 2005 01:36:06 +0000 (GMT) (envelope-from peadar.edwards@gmail.com) Received: by wproxy.gmail.com with SMTP id 58so77052wri for ; Tue, 04 Jan 2005 17:36:06 -0800 (PST) DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=beta; d=gmail.com; h=received:message-id:date:from:reply-to:to:subject:in-reply-to:mime-version:content-type:content-transfer-encoding:references; b=seT72WDE6vAiMUjqlcnmZD5vtH/tRaZsC590lCMfLN6WpwK5IwhD1M7+iiXuh9eE1EyjMTIG0AHfdkHhjUyyacnCi2WZ9JnLF0eMPMSxmHePMseQociORN7Oi8SmXMjgrQ1iIFXblqf8lsiuFgm/XCu54hyRFgNGWon3XuX9ju4= Received: by 10.54.49.64 with SMTP id w64mr36510wrw; Tue, 04 Jan 2005 17:36:06 -0800 (PST) Received: by 10.54.57.76 with HTTP; Tue, 4 Jan 2005 17:36:06 -0800 (PST) Message-ID: <34cb7c840501041736570afdfa@mail.gmail.com> Date: Wed, 5 Jan 2005 01:36:06 +0000 From: Peter Edwards To: Julian Elischer , current@freebsd.org In-Reply-To: <41DAF53A.5000300@elischer.org> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit References: <41DA2AE0.3020108@elischer.org> <20050104.032929.102142020.imp@bsdimp.com> <20050104114308.D30830@maren.thelosingend.net> <41DAF53A.5000300@elischer.org> Subject: Re: Is there a boot sector guru in the house? X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list Reply-To: peadar@freebsd.org List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 05 Jan 2005 01:36:07 -0000 I don't have a box I can test this on, but this looks like a definite candidate to get 3 more bytes: --- boot0.S 24 Nov 2004 15:39:04 -0000 1.12 +++ boot0.S 5 Jan 2005 01:27:31 -0000 @@ -314,8 +314,7 @@ cmpw $MAGIC,0x1fe(%bx) # Bootable? jne main.10 # No pushw %si # Save - movw $crlf,%si # Leave some - callw puts # space + callw putn # Leave space popw %si # Restore jmp *%bx # Invoke bootstrap If my arithmetic is correct, that leaves us wanting one more byte. I don't get the save/restore of %si at the end, and judging by the comment, someone else didn't either. It could be of some use to the chained loader, but our boot1.S doesn't do anything with it.