From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S263401AbTJQKYq (ORCPT ); Fri, 17 Oct 2003 06:24:46 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S263411AbTJQKYq (ORCPT ); Fri, 17 Oct 2003 06:24:46 -0400 Received: from users.linvision.com ([62.58.92.114]:20639 "HELO bitwizard.nl") by vger.kernel.org with SMTP id S263401AbTJQKYn (ORCPT ); Fri, 17 Oct 2003 06:24:43 -0400 Date: Fri, 17 Oct 2003 12:24:36 +0200 From: Rogier Wolff To: Norman Diamond Cc: Hans Reiser , Wes Janzen , Rogier Wolff , John Bradford , linux-kernel@vger.kernel.org, nikita@namesys.com, Pavel Machek Subject: Re: Blockbusting news, this is important (Re: Why are bad disk sectors numbered strangely, and what happens to them?) Message-ID: <20031017102436.GB10185@bitwizard.nl> References: <32a101c3916c$e282e330$5cee4ca5@DIAMONDLX60> <200310131014.h9DAEwY3000241@81-2-122-30.bradfords.org.uk> <33a201c39174$2b936660$5cee4ca5@DIAMONDLX60> <20031014064925.GA12342@bitwizard.nl> <3F8BA037.9000705@sbcglobal.net> <3F8BBC08.6030901@namesys.com> <11bf01c39492$bc5307c0$3eee4ca5@DIAMONDLX60> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <11bf01c39492$bc5307c0$3eee4ca5@DIAMONDLX60> User-Agent: Mutt/1.3.28i Organization: BitWizard.nl Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Oct 17, 2003 at 06:40:01PM +0900, Norman Diamond wrote: > I explained to them why the LBA sector number should still get > reallocated even though the data are lost. This is unbelievably bad: Sometimes it is worth it, to try and read the block again and again. We've seen blocks getting read after we've retried over 1000 times from "userspace". That doesn't include the retries that the drive did for us "behind the scenes". If you manage to convince Toshiba to remap the sector on a "bad read", we'll never ever be able to recover the sector. We've also been able to provide a different environment (e.g. other ambient temperature) to a drive so that previously bad sectors could be read. No, the only way is to realloc on write. (but it should remember that the data was bad, and treat the physical area with extra caution. It's possible that something happened while writing that sector, so that rewriting it this time will fix the problem for good, but on the other hand, that area of the drive demonstrated the abilitty to lose data, so you shouldn't trust any data to it!) Roger. -- ** R.E.Wolff@BitWizard.nl ** http://www.BitWizard.nl/ ** +31-15-2600998 ** *-- BitWizard writes Linux device drivers for any device you may have! --* **** "Linux is like a wigwam - no windows, no gates, apache inside!" ****