Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757446Ab2BMRxq (ORCPT ); Mon, 13 Feb 2012 12:53:46 -0500 Received: from rcsinet15.oracle.com ([148.87.113.117]:48777 "EHLO rcsinet15.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755584Ab2BMRxp (ORCPT ); Mon, 13 Feb 2012 12:53:45 -0500 To: Mike Snitzer Cc: "Martin K. Petersen" , linux-scsi@vger.kernel.org, James Bottomley , Hannes Reinecke , linux-kernel@vger.kernel.org Subject: Re: scsi_error: do not allow IO errors with certain ILLEGAL_REQUEST sense to be retryable From: "Martin K. Petersen" Organization: Oracle References: <1322857889-2623-1-git-send-email-snitzer@redhat.com> <20111206212704.GB30719@redhat.com> <20111206224218.GA31543@redhat.com> <20120213162923.GA29578@redhat.com> Date: Mon, 13 Feb 2012 12:53:29 -0500 In-Reply-To: <20120213162923.GA29578@redhat.com> (Mike Snitzer's message of "Mon, 13 Feb 2012 11:29:24 -0500") Message-ID: User-Agent: Gnus/5.110017 (No Gnus v0.17) Emacs/23.2 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-Source-IP: ucsinet21.oracle.com [156.151.31.93] X-CT-RefId: str=0001.0A090208.4F394E20.010F,ss=1,re=0.000,fgs=0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1938 Lines: 42 >>>>> "Mike" == Mike Snitzer writes: Mike> So that makes 3 different _prominent_ storage vendors, that I am Mike> aware of, that are bitten by their broken storage (relative to Mike> discard and properly advertising which variant they actually Mike> support). I'd much rather deal with the storage vendors (or their Mike> customers) reporting that discards aren't working than mutual Mike> customers reporting that they cannot even install to the storage. More graceful handling of the sense data aside, we do have a couple of options: 1. Now that the provisioning portion seems to be stable in SBC-3 we can nuke the interim spec heuristics and only support devices that report the right thing. This may disable provisioning for some existing users whose arrays run non-compliant firmware. 2. We can add another layer of heuristics based on the RSOC wrapper I introduced for write same. Maybe you could send me sg_opcodes output for the arrays in question? Mike> The ultimate fix is clear: storage vendors need to fix their Mike> storage (2 of the 3 have, 1 is working on it). But a Linux-only Mike> workaround for this series of unfortunate events (particularly as Mike> it happens with multipath in the mix) is to have SCSI classify Mike> certain ILLEGAL_REQUEST as the TARGET_ERROR that they are. I don't have a fundamental problem with your patch. But since we explicitly handle ILLEGAL REQUEST with 0x20 and 0x24 in sd.c I wonder what's broken? We should disable discard support if the WRITE SAME w/ UNMAP fails. I'll see if I can figure out what's going on unless you beat me to it... -- Martin K. Petersen Oracle Linux Engineering -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/