From owner-freebsd-bugs@FreeBSD.ORG Tue Mar 25 11:35:53 2008 Return-Path: Delivered-To: freebsd-bugs@FreeBSD.ORG Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 40239106566C; Tue, 25 Mar 2008 11:35:53 +0000 (UTC) (envelope-from tektonaut@fuckner.net) Received: from dedihh.fuckner.net (dedihh.fuckner.net [81.209.183.161]) by mx1.freebsd.org (Postfix) with ESMTP id EBA3F8FC1A; Tue, 25 Mar 2008 11:35:52 +0000 (UTC) (envelope-from tektonaut@fuckner.net) Received: from localhost (localhost [127.0.0.1]) by dedihh.fuckner.net (Postfix) with ESMTP id 5944061D07; Tue, 25 Mar 2008 12:19:25 +0100 (CET) X-Virus-Scanned: amavisd-new at fuckner.net Received: from dedihh.fuckner.net ([127.0.0.1]) by localhost (dedihh.fuckner.net [127.0.0.1]) (amavisd-new, port 10024) with SMTP id hCoSQjv5Mlc7; Tue, 25 Mar 2008 12:19:18 +0100 (CET) Received: from ranger.local (e176129158.adsl.alicedsl.de [85.176.129.158]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by dedihh.fuckner.net (Postfix) with ESMTPSA id 22AD761CD2; Tue, 25 Mar 2008 12:19:18 +0100 (CET) Message-ID: <47E8DFB5.1020503@fuckner.net> Date: Tue, 25 Mar 2008 12:19:17 +0100 From: Tektonaut User-Agent: Thunderbird 2.0.0.12 (Macintosh/20080213) MIME-Version: 1.0 To: remko@FreeBSD.ORG, freebsd-bugs@FreeBSD.ORG, sos@FreeBSD.ORG, Adam Pordzik References: <200803140710.m2E7A0IM079653@freefall.freebsd.org> <20080324213323.GA87260@zim.MIT.EDU> In-Reply-To: <20080324213323.GA87260@zim.MIT.EDU> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: Subject: Re: kern/121686: [ata]: bogus CHS to LBA mapping in (at least) ata X-BeenThere: freebsd-bugs@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Bug reports List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 25 Mar 2008 11:35:53 -0000 David Schultz wrote: > This is a problem with some CD-ROMs, too, except in the case of > CD-ROMs, the problem is more fundamental: the official standard > allows the drive to overestimate the disc's capacity by a few > sectors. Sounds like the drives are guessing the correct sector count... > GEOM just exacerbates the problem by having a dozen > different providers each try to read the last sector. The latter > issue has been discussed and the general reaction is that it's > undesirable to force GEOM providers to cope with misbehaving > devices. I can't see any problem here. Of course, GEOM should never try to work arounf hardware issues, imho. Nobody would argue against a disk with broken sector zero. > The fact that these errors result in a timeout in FreeBSD but not > under (at least) Solaris makes me wonder whether there isn't a > better way for the ata driver to notice the error than a timeout. > Then again, I'm not an expert on ata. Maybe. But here the last sector definitively is readable, e.g. I can access this CF-Card with da(4) via umass in a card-reader. As I understand ata-disk.c, it uses fixed and pre-defined values for heads and sectors/track to calculate overall cylinder count. Since this mapping also appears in ata-all.c, I have no idea where to fix it. (Didn't looked in ata-raid.c) Soren, did already you found some time to look at it? Why there is a need to "think" in CHS at all? Regards, Adam --