From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christoph Hellwig Subject: Re: CONFIG_DM_MQ_DEFAULT makes my kernel unhappy.. Date: Sun, 26 Apr 2015 07:16:28 -0700 Message-ID: <20150426141628.GA7085@infradead.org> References: <20150425092358.GA15550@infradead.org> <20150425152856.GB28453@redhat.com> <20150425153732.GA10612@infradead.org> Reply-To: device-mapper development Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <20150425153732.GA10612@infradead.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: dm-devel-bounces@redhat.com Errors-To: dm-devel-bounces@redhat.com To: Mike Snitzer Cc: Christoph Hellwig , dm-devel@redhat.com List-Id: dm-devel.ids On Sat, Apr 25, 2015 at 08:37:32AM -0700, Christoph Hellwig wrote: > I'll give it a spin. > > > What were you actually testing when this happened? Were you failing > > paths under IO load or something? > > This happened on the initial udev-direct scan of the devices. > > > Also, which upstream commit was your tree based on? Did you have any > > non-upstream patches applied that I should be aware of? > > Latest Linus tree as of this morning. Seems like the first warning goes away without CONFIG_DEBUG_OBJECTS. Note that in either way I/O over dm-mpath actually works fine. Btw, this is the script used to reproduce it, you need CONFIG_TARGET_CORE, CONFIG_TCM_IBLOCK and CONFIG_LOOPBACK_TARGET enabled. It jsut creates two different targets with a lun each, pointing to the same device. The target code automatically supports ALUA in this case. --- #!/bin/bash # add your own device #DEV=/dev/sda mount -t configfs none /sys/kernel/config/ tcm_node --block iblock_0/array /dev/sda line=$(tcm_loop --createnexus=0) wwn=$(echo $line | awk '{print $15}') tcm_loop --addlun=$wwn 0 0 iblock_0/array line=$(tcm_loop --createnexus=1) wwn=$(echo $line | awk '{print $15}') tcm_loop --addlun=$wwn 1 0 iblock_0/array