From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mark Lord Subject: Re: [PATCH] sata_mv: Fix broken Marvell 7042 support. Date: Wed, 05 Dec 2007 18:35:16 -0500 Message-ID: <475735B4.7020401@rtr.ca> References: <4751A2DA.6030403@rtr.ca> <20071203154749.6lah7pulw8ow0s84@email.syntomax.com> <47543C58.4040106@rtr.ca> <475447A0.2010101@rtr.ca> <47544B3C.2010901@rtr.ca> <1196712661.6362.5.camel@liza> <475465F7.7050705@rtr.ca> <1196714235.6362.9.camel@liza> <47546CF6.30301@rtr.ca> <1196722124.6362.17.camel@liza> <20071203231057.39ae9b71@the-village.bc.nu> <1196726490.6362.21.camel@liza> <47549A26.6080900@rtr.ca> <1196727475.6362.27.camel@liza> <47549E0B.9070509@rtr.ca> <1196812599.6909.10.camel@liza> <47572A18.2010904@rtr.ca> <475732C0.2090901@rtr.ca> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from rtr.ca ([76.10.145.34]:4736 "EHLO mail.rtr.ca" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751439AbXLEXfS (ORCPT ); Wed, 5 Dec 2007 18:35:18 -0500 In-Reply-To: <475732C0.2090901@rtr.ca> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Hein-Pieter van Braam Cc: Alan Cox , "Morrison, Tom" , IDE/ATA development list , Jeff Garzik , Tejun Heo , Alan Cox Mark Lord wrote: > Mark Lord wrote: >> Hein-Pieter van Braam wrote: >>> I zero'd all the disks, and now they show up as 'new' in the highpoint >>> BIOS again... so, I guess there IS some reserved part somewhere that's >>> accessible with the sata_mv driver. >> .. >> >> Yeah, that's my suspicion too.. they must have just simply moved >> the metadata to near the end instead of sector-8. >> >> Mmm... I'll try a smaller drive here, >> and zero the entire drive, then reboot with it >> on the Highpoint board, and then see what sector it modified. >> >> This'll take a while. > .. > > Actually, it doesn't take long at all, > with some creative use of fdisk. > > And I haven't yet figured out their logic, > but here's what I've found. > > They write their RAID metadata near-ish to the end of the drive. > On my 320GB drives, it ended up at about -199853 sectors from > the end of the drive. I have no idea what logic leads to them > choosing such a peculiar location for it. .. Correction: Metadata begins at sector -191192 on my drive. > > That's NOT an even cylinder or anything else I can figure out. > > But if you leave the last 100KB of the drive unallocated for any > partitions, then your data might survive. > > This needs more research, and probably another patch of some kind > in the driver for #upstream-fixes. I'm busy with a course all week, > this won't happen (from me) until the weekend. > > What a screwy BIOS.