From owner-freebsd-hackers Tue Oct 13 18:15:23 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id SAA08888 for freebsd-hackers-outgoing; Tue, 13 Oct 1998 18:15:23 -0700 (PDT) (envelope-from owner-freebsd-hackers@FreeBSD.ORG) Received: from smtp01.primenet.com (smtp01.primenet.com [206.165.6.131]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id SAA08879 for ; Tue, 13 Oct 1998 18:15:19 -0700 (PDT) (envelope-from tlambert@usr08.primenet.com) Received: (from daemon@localhost) by smtp01.primenet.com (8.8.8/8.8.8) id SAA01640; Tue, 13 Oct 1998 18:15:01 -0700 (MST) Received: from usr08.primenet.com(206.165.6.208) via SMTP by smtp01.primenet.com, id smtpd001601; Tue Oct 13 18:14:53 1998 Received: (from tlambert@localhost) by usr08.primenet.com (8.8.5/8.8.5) id SAA21361; Tue, 13 Oct 1998 18:14:50 -0700 (MST) From: Terry Lambert Message-Id: <199810140114.SAA21361@usr08.primenet.com> Subject: Re: BETA problems... To: mike@smith.net.au (Mike Smith) Date: Wed, 14 Oct 1998 01:14:50 +0000 (GMT) Cc: karpen@ocean.campus.luth.se, hackers@FreeBSD.ORG In-Reply-To: <199810130120.SAA01157@dingo.cdrom.com> from "Mike Smith" at Oct 12, 98 06:20:39 pm X-Mailer: ELM [version 2.4 PL25] MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG > > _Is_ it fixed in new boot code, perhaps? > > No. It's almost impossible to get the distinction right. > > The difficulty lies in working out which physical drives the BIOS > numbers correspond to. Unless you have a *very* new system, there is > simply no way to know that the BIOS drive 0x81 is in fact wd2. In > order for this to work, the user has to provide the missing data, > either by typing 1:wd(2a)kernel every time (tedious) or putting it in > /boot.config. Actually, you could MD5 the first N sectors of the disk using both VM86() I/O and kernel I/O, and if the MD5 matched, you've found your drive. If you have two drives that MD5 the same, tweak an unused portion of one of them using VM86() I/O and see which one got tweaked using kernel I/O, and, again, you've found your drive. It's *not* impossible, since this is how Windows 95/98 converts fd's opened using the INT 21 based I/O in AUTOEXEC.BAT to fd's that, when INT 21 I/O is done to them in protected mode (via thunk) into calls to the protected mode disk drivers and IFS layer (VFAT, VFAT32, etc.) instead. Terry Lambert terry@lambert.org --- Any opinions in this posting are my own and not those of my present or previous employers. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message