From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Disseldorp Date: Wed, 02 Sep 2020 22:23:36 +0000 Subject: Re: [RFC PATCH] scsi: target: detect XCOPY NAA descriptor conflicts Message-Id: <20200903002336.083e88a4@suse.de> List-Id: References: <20200813002142.13820-1-ddiss@suse.de> <2155E745-0E65-441B-93AF-7B4C0A53F5F4@oracle.com> In-Reply-To: <2155E745-0E65-441B-93AF-7B4C0A53F5F4@oracle.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Michael Christie Cc: target-devel@vger.kernel.org, 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