From mboxrd@z Thu Jan 1 00:00:00 1970 From: Douglas Gilbert Subject: Re: [PATCH 1/3] SCSI: rearrange code in scsi_io_completion Date: Wed, 01 Oct 2008 16:08:37 +0200 Message-ID: <48E38465.1070101@interlog.com> References: Reply-To: dgilbert@interlog.com Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from elrond2.infotech.no ([82.134.31.41]:46463 "EHLO elrond2.infotech.no" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752675AbYJAOQZ (ORCPT ); Wed, 1 Oct 2008 10:16:25 -0400 In-Reply-To: Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: Alan Stern Cc: "Martin K. Petersen" , James Bottomley , SCSI development list Alan Stern wrote: > On Tue, 30 Sep 2008, Martin K. Petersen wrote: > >>>>>>> "Alan" == Alan Stern writes: >> Alan> Are there types of failure for which we really don't want to >> Alan> print anything? For example, what about UNIT ATTENTION for >> Alan> media changes or the DIX/DIF failures (should those both be >> Alan> DIF?)? >> >> ILLEGAL REQUEST + 10/[123] indicates that the HBA rejected the request >> (DIX). >> >> ABORTED COMMAND + 10/[123] indicates that the device found a >> corruption error (DIF). > > That answer the parenthetical question. Do you know the answer to the > main question? That is, when either of these events occurs do we want > to skip adding an error message to the system log? I know that SAS maps certain types of transport errors to "ABORTED COMMAND" (see http://www.t10.org/ftp/t10/drafts/sas2/sas2r14e.pdf section 10.2.3) and they should be retried, especially the timeouts. For example, if there are 20 disks hanging off a SAS expander with a 4 wide link back to the host, then issuing big and very frequent READs to those 20 disks should see some "ABORTED COMMAND"s. Doug Gilbert