From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dave Olien Subject: Re: Question about Request Sense case in scsi_lib.c Date: Wed, 13 Oct 2004 10:56:55 -0700 Sender: linux-scsi-owner@vger.kernel.org Message-ID: <20041013175655.GA30013@osdl.org> References: <20041012000058.GA26569@osdl.org> <20041012165919.GA27526@osdl.org> <1097601199.2044.91.camel@mulgrave> <416C8E8D.7050000@torque.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from fw.osdl.org ([65.172.181.6]:48573 "EHLO mail.osdl.org") by vger.kernel.org with ESMTP id S269768AbUJMR53 (ORCPT ); Wed, 13 Oct 2004 13:57:29 -0400 Content-Disposition: inline In-Reply-To: <416C8E8D.7050000@torque.net> List-Id: linux-scsi@vger.kernel.org To: Douglas Gilbert Cc: James Bottomley , Tim Pepper , SCSI Mailing List Here's what seeing out of the SCSI log: command = Write (10) 00 00 00 84 00 00 04 00 00 Current sdx: sense key Unit Attention ASC=8b ASCQ= 2 P<6>scsi <2:0:2:3> done SUCCESS 2 scsi2 : destination target 2, lun 3 command = Write (10) 00 00 00 88 00 00 04 00 00 Current sdx: sense key Unit Attention ASC=8b ASCQ= 2 P<6>scsi <2:0:2:0> done SUCCESS 2 scsi2 : destination target 2, lun 0 command = Write (10) 00 00 00 00 48 00 04 00 00 Current sdu: sense key Unit Attention ASC=8b ASCQ= 2 P<3>Incorrect number of segments after building list counted 11, received 5 req nr_sec 1024, cur_nr_sec 8 On Wed, Oct 13, 2004 at 12:10:21PM +1000, Douglas Gilbert wrote: > UNIT ATTENTION and NOT READY are both sense keys so a > device can't yield both on one command. However you may be > on the right track as there is an ever increasing number of > reasons a device could issue a UNIT ATTENTION. [See SPC-3 > rev 21 and I believe these ASC codes (and all their associated > ASCQ codes) occur with a sense key of UNIT ATTENTION: > 0x28, 0x29, 0x2a, 0x3f, 0x5b/0x1 and 0x5d.] > > Unlikely in this case but a sense key of UNIT ATTENTION > (or perhaps RECOVERED ERROR) with an additional sense > of "Hardware impending failure, seek error rate too high" > may slip by without even a log entry. > > >As for the error, I still don't understand that, but it looks like > >something went wrong in setting up or tearing down the dma mapping, so > >that it was incorrectly described when this happened a second time. > > I hope to address the code in the scsi_io_completion() error/warning > processing paths with the descriptor_sense cleanup. There seems to > be a missing scsi_print_sense() call on the UNIT ATTENTION path. > > Dave, does your log show a bus error (ASC/ASCQ=0x29/0x2) has occurred? > > Doug Gilbert