From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.0 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 817F9C433E7 for ; Wed, 2 Sep 2020 22:23:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5B923207D3 for ; Wed, 2 Sep 2020 22:23:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726377AbgIBWXj (ORCPT ); Wed, 2 Sep 2020 18:23:39 -0400 Received: from mx2.suse.de ([195.135.220.15]:58940 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726226AbgIBWXj (ORCPT ); Wed, 2 Sep 2020 18:23:39 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id B7518AC55; Wed, 2 Sep 2020 22:23:38 +0000 (UTC) Date: Thu, 3 Sep 2020 00:23:36 +0200 From: David Disseldorp To: Michael Christie Cc: target-devel@vger.kernel.org, linux-scsi@vger.kernel.org Subject: Re: [RFC PATCH] scsi: target: detect XCOPY NAA descriptor conflicts Message-ID: <20200903002336.083e88a4@suse.de> In-Reply-To: <2155E745-0E65-441B-93AF-7B4C0A53F5F4@oracle.com> References: <20200813002142.13820-1-ddiss@suse.de> <2155E745-0E65-441B-93AF-7B4C0A53F5F4@oracle.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-scsi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org Hi Mike, On Tue, 1 Sep 2020 22:17:51 -0500, Michael Christie wrote: > > --- a/drivers/target/target_core_xcopy.c > > +++ b/drivers/target/target_core_xcopy.c > > @@ -68,8 +68,14 @@ static int target_xcopy_locate_se_dev_e4_iter(struct se_device *se_dev, > > if (rc != 0) > > return 0; > > > > - info->found_dev = se_dev; > > pr_debug("XCOPY 0xe4: located se_dev: %p\n", se_dev); > > + if (info->found_dev) { > > + pr_warn("XCOPY 0xe4 descriptor conflict for se_dev %p and %p\n", > > + info->found_dev, se_dev); > > + target_undepend_item(&info->found_dev->dev_group.cg_item); > > + return -ENOTUNIQ; > > + } > > + info->found_dev = se_dev; > > Was it valid to copy to/from the same LUN? You would copy from/to different src/destinations on that LUN. Would your patch break that? XCOPY allows for copies to occur on the same LUN or between separate src/destinations. The intention of this patch is that regardless of the source or destination, if the NAA WWN could refer to multiple LUNs on the same target (via target_for_each_device()) then the XCOPY should fail and force the initiator to fallback to initiator driver copy. Cheers, David