From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S265353AbTL2UUt (ORCPT ); Mon, 29 Dec 2003 15:20:49 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S265147AbTL2UU0 (ORCPT ); Mon, 29 Dec 2003 15:20:26 -0500 Received: from imap.gmx.net ([213.165.64.20]:7076 "HELO mail.gmx.net") by vger.kernel.org with SMTP id S265112AbTL2URd (ORCPT ); Mon, 29 Dec 2003 15:17:33 -0500 X-Authenticated: #552865 Date: Mon, 29 Dec 2003 21:24:32 +0100 From: Florian Schuele To: linux-kernel@vger.kernel.org Subject: Re: Is it safe to ignore UDMA BadCRC errors? Message-ID: <20031229202432.GA8418@spacken.de> References: <16368.20794.147453.255239@jik.kamens.brookline.ma.us> <20031229195235.GC26821@bounceswoosh.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20031229195235.GC26821@bounceswoosh.org> X-PGP-KeyID: 0xBBCE086E User-Agent: Mutt/1.5.4i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On 29.12.03 12:52 -0700, Eric D. Mudama wrote: > On Mon, Dec 29 at 11:07, Jonathan Kamens wrote: > >The topic of CRC errrors from IDE drives has been discussed numerous > >times on this list, and I've reviewed those discussions, but I'm still > >not 100% certain of the answer to this question: Is it safe for me to > >ignore occasional CRC errors from my drive? > > > >Here are the details.... > > > >The errors look like this: > > > > hde: dma_intr: status=0x51 { DriveReady SeekComplete Error } > > hde: dma_intr: error=0x84 { DriveStatusError BadCRC } > > > >They don't seem to happen often enough to convince the kernel to back > >down to a slower UDMA mode. > > 0x5184 is the error code for when the drive sends you data that was > corrupted during transmission over the cable. In general, nothing is > wrong with your drive, and a re-read from the drive will almost always > produce the proper data. > > Odds are your cable is bad, regardless of how "good" it looks, you > really can't tell if you have marginal conductivity on a pin or > something else wierd. In my home system I replace the IDE cables > every few years, on my test box at work I replace them every month > since I'm doing lots of re-plugging of drives. Note that a bad cable > is *dangerous* to your filesystem, since a PIO transfer to the drive > has *no* integrity checking on the cable! > > Also, those "round" cables violate the ATA spec, I can't really > recommend using them unless airflow is your #1 concern, however in > that case you're probably better off buying a SATA drive. > > Generic IDE ribbon cables (between 6" and 18") seem to work fine for > most people, just go buy another $2 cable from CompUSA and see if the > problem goes away. > > FYI, UDMA4 isn't that fast, only 66MB/sec... "good" (functional, not > brand name) flat cables should be able to do 100MB sec trivially. i wrote a mail to this list a few days ago. i have the same error messages as the above. but _only_ with kernel 2.6.0, _not_ with 2.4.20 ... thats strange. isnt it? after i little traffic on the hd`s the system freezes. -- florian schuele