From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Subject: Re: block: don't check request size in blk_cloned_rq_check_limits() To: Mike Snitzer References: <1464593093-93527-1-git-send-email-hare@suse.de> <20160610131901.GA28570@redhat.com> Cc: Jens Axboe , Brian King , linux-scsi@vger.kernel.org, linux-block@vger.kernel.org, mark.bergman@uphs.upenn.edu, "Martin K. Petersen" From: Hannes Reinecke Message-ID: <575AC10F.7020504@suse.de> Date: Fri, 10 Jun 2016 15:30:55 +0200 MIME-Version: 1.0 In-Reply-To: <20160610131901.GA28570@redhat.com> Content-Type: text/plain; charset=windows-1252 List-ID: On 06/10/2016 03:19 PM, Mike Snitzer wrote: > On Mon, May 30 2016 at 3:24am -0400, > Hannes Reinecke wrote: > >> When checking a cloned request there is no need to check >> the overall request size; this won't have changed even >> when resubmitting to another queue. >> Without this patch ppc64le on ibmvfc fails to boot. > > By simply removing the check aren't you papering over the real problem? > Looking at Martin's commit f31dc1cd490539 (which introduced the current > variant of the limits check) I'm not convinced it is equivalent to what > he replaced. I'll look closer in a bit. > The check itself is wrong, as we need (at least) to check the max_hw_sectors here; the request is already fully assembled, so there is a really good chance he's going beyond the max_sectors. But trying the error still was found to be present. So I decided to rip it out, as the overall value of this check is zero. > Also you categorized your fix was for "ppc64le on ibmvfc"; whereas Mark > has reported this issue (off-list) against x86_64. By making it seem > ppc64le specific I didn't take this patch to be generally applicable. > Well, it has been observed on ppc64. That doesn't mean _only_ ppc64 is affected. If it were ppc64 only it should've been marked as such, right? Cheers, Hannes -- Dr. Hannes Reinecke Teamlead Storage & Networking hare@suse.de +49 911 74053 688 SUSE LINUX GmbH, Maxfeldstr. 5, 90409 N�rnberg GF: F. Imend�rffer, J. Smithard, J. Guild, D. Upmanyu, G. Norton HRB 21284 (AG N�rnberg) From mboxrd@z Thu Jan 1 00:00:00 1970 From: Hannes Reinecke Subject: Re: block: don't check request size in blk_cloned_rq_check_limits() Date: Fri, 10 Jun 2016 15:30:55 +0200 Message-ID: <575AC10F.7020504@suse.de> References: <1464593093-93527-1-git-send-email-hare@suse.de> <20160610131901.GA28570@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Received: from mx2.suse.de ([195.135.220.15]:48612 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753392AbcFJNcZ (ORCPT ); Fri, 10 Jun 2016 09:32:25 -0400 In-Reply-To: <20160610131901.GA28570@redhat.com> Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: Mike Snitzer Cc: Jens Axboe , Brian King , linux-scsi@vger.kernel.org, linux-block@vger.kernel.org, mark.bergman@uphs.upenn.edu, "Martin K. Petersen" On 06/10/2016 03:19 PM, Mike Snitzer wrote: > On Mon, May 30 2016 at 3:24am -0400, > Hannes Reinecke wrote: >=20 >> When checking a cloned request there is no need to check >> the overall request size; this won't have changed even >> when resubmitting to another queue. >> Without this patch ppc64le on ibmvfc fails to boot. >=20 > By simply removing the check aren't you papering over the real proble= m? > Looking at Martin's commit f31dc1cd490539 (which introduced the curre= nt > variant of the limits check) I'm not convinced it is equivalent to wh= at > he replaced. I'll look closer in a bit. >=20 The check itself is wrong, as we need (at least) to check the max_hw_sectors here; the request is already fully assembled, so there i= s a really good chance he's going beyond the max_sectors. But trying the error still was found to be present. So I decided to rip it out, as the overall value of this check is zero. > Also you categorized your fix was for "ppc64le on ibmvfc"; whereas Ma= rk > has reported this issue (off-list) against x86_64. By making it seem > ppc64le specific I didn't take this patch to be generally applicable. >=20 Well, it has been observed on ppc64. That doesn't mean _only_ ppc64 is affected. If it were ppc64 only it should've been marked as such, right= ? Cheers, Hannes --=20 Dr. Hannes Reinecke Teamlead Storage & Networking hare@suse.de +49 911 74053 688 SUSE LINUX GmbH, Maxfeldstr. 5, 90409 N=FCrnberg GF: F. Imend=F6rffer, J. Smithard, J. Guild, D. Upmanyu, G. Norton HRB 21284 (AG N=FCrnberg) -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" i= n the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html