From owner-freebsd-hackers@FreeBSD.ORG Wed Aug 11 11:37:59 2010 Return-Path: Delivered-To: hackers@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 6AB3C1065679 for ; Wed, 11 Aug 2010 11:37:59 +0000 (UTC) (envelope-from netch@segfault.kiev.ua) Received: from segfault.kiev.ua (segfault.kiev.ua [193.193.193.4]) by mx1.freebsd.org (Postfix) with ESMTP id CB8EC8FC1D for ; Wed, 11 Aug 2010 11:37:58 +0000 (UTC) Received: from segfault.kiev.ua (localhost.segfault.kiev.ua [127.0.0.1]) by segfault.kiev.ua (8.14.4/8.14.4/8.Who.Cares) with ESMTP id o7BBbvee001151 for ; Wed, 11 Aug 2010 14:37:57 +0300 (EEST) (envelope-from netch@segfault.kiev.ua) Received: (from netch@localhost) by segfault.kiev.ua (8.14.4/8.14.4/Submit) id o7BBbqCq001148 for hackers@freebsd.org; Wed, 11 Aug 2010 14:37:52 +0300 (EEST) (envelope-from netch) Resent-From: netch@netch.kiev.ua Resent-Date: Wed, 11 Aug 2010 14:37:52 +0300 Resent-Message-ID: <20100811113752.GA1075@netch.kiev.ua> Resent-To: hackers@freebsd.org Date: Wed, 11 Aug 2010 14:15:20 +0300 From: Valentin Nechayev To: freebsd-hackers@freebsd.org Message-ID: <20100811111520.GF17926@netch.kiev.ua> References: <20100811060439.GD17926@netch.kiev.ua> <4C624B90.3040101@yandex.ru> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <86bp99eccg.fsf@ds4.des.no> X-42: On Cc: Subject: Re: Support for WD Advanced Format disks X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list Reply-To: netch@netch.kiev.ua List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 11 Aug 2010 11:37:59 -0000 >>>>> des@ wrote: > There's a jumper setting for > "Windows XP compatibility", but apparently, it only affects the (fake) > geometry the disk reports to the BIOS. No, this jumper internally increases any linear block number learned from bus request by 1. I.e. the block number 1 without this jumper is seen as block number 0 with this jumper, and so on. So with this jumper, block 63 (internally it is 64) is at begin of physical sector. These data are from my own tests with WD15EARS, see links earlier. I didn't see any difference in fake reported geometry - moreover, with this WD15EARS instance all 512 bytes of identification page were equal with or without jumper. As I already told, it didn't shorten reported size and any tool which tries to read last block (RAID check, GPT reading) had failed with I/O error. I guess this is temporary error and future firmware editions would fix it. -netch-