From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mark Lord Subject: Re: [PATCH] scsi_lib.c: continue after MEDIUM_ERROR Date: Wed, 31 Jan 2007 13:37:56 -0500 Message-ID: <45C0E204.3030901@rtr.ca> References: <200701301947.08478.liml@rtr.ca> <1170206199.10890.13.camel@mulgrave.il.steeleye.com> <311601c90701301725n53d25a74g652b7ca3bfc64c56@mail.gmail.com> <45BFF3D6.9050605@rtr.ca> <45C00AEE.1090708@emc.com> <45C0B0DC.8030501@rtr.ca> <20070131152301.19a8a5ac@localhost.localdomain> <45C0D8A1.2030506@rtr.ca> <1170267198.3402.58.camel@mulgrave.il.steeleye.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1170267198.3402.58.camel@mulgrave.il.steeleye.com> Sender: linux-scsi-owner@vger.kernel.org To: James Bottomley Cc: Alan , Ric Wheeler , "Eric D. Mudama" , linux-kernel@vger.kernel.org, IDE/ATA development list , linux-scsi , dougg@torque.net List-Id: linux-ide@vger.kernel.org James Bottomley wrote: > On Wed, 2007-01-31 at 12:57 -0500, Mark Lord wrote: >> Alan wrote: >>>> When libata reports a MEDIUM_ERROR to us, we *know* it's non-recoverable, >>>> as the drive itself has already done internal retries (libata uses the >>>> "with retry" ATA opcodes for this). >>> This depends on the firmware. Some of the "raid firmware" drives don't >>> appear to do retries in firmware. >> One way to tell if this is true, is simply to time how long >> the failed operation takes. If the drive truly does not do retries, >> then the media error should be reported more or less instantly >> (assuming drive was already spun up). > > Well, the simpler way (and one we have a hope of implementing) is to > examine the ASC/ASCQ codes to see if the error is genuinely unretryable. My suggestion above was not for a kernel fix, but rather just as a way of determining if drives which claim "no retries" actually do them or not. :) > I seem to have dropped the ball on this one in that the scsi_error.c > pieces of this patch > > http://marc.theaimsgroup.com/?l=linux-scsi&m=116485834119885 > > I thought I'd applied. Apparently I didn't, so I'll go back and put > them in. Good. That would be a useful supplement to the patch I posted here. Cheers