From mboxrd@z Thu Jan 1 00:00:00 1970 From: Keith Busch Subject: Re: hch's native NVMe multipathing [was: Re: [PATCH 1/2] Don't blacklist nvme] Date: Thu, 16 Feb 2017 13:07:43 -0500 Message-ID: <20170216180742.GC17828@localhost.localdomain> References: <1487107154-24883-1-git-send-email-keith.busch@intel.com> <20170215145617.GA4241@infradead.org> <20170216025357.GA9241@redhat.com> <20170216142621.GA21972@infradead.org> <20170216151337.GA12678@redhat.com> <20170216173856.GB17828@localhost.localdomain> <1487266648.2612.3.camel@sandisk.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from mga14.intel.com ([192.55.52.115]:37166 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932576AbdBPR7m (ORCPT ); Thu, 16 Feb 2017 12:59:42 -0500 Content-Disposition: inline In-Reply-To: <1487266648.2612.3.camel@sandisk.com> Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: Bart Van Assche Cc: "snitzer@redhat.com" , "dm-devel@redhat.com" , "hch@infradead.org" , "linux-nvme@lists.infradead.org" , "linux-scsi@vger.kernel.org" On Thu, Feb 16, 2017 at 05:37:41PM +0000, Bart Van Assche wrote: > On Thu, 2017-02-16 at 12:38 -0500, Keith Busch wrote: > > Maybe I'm not seeing the bigger picture. Is there some part to multipath > > that the kernel is not in a better position to handle? > > Does this mean that the code to parse /etc/multipath.conf will be moved into > the kernel? Or will we lose the ability to configure the policies that > /etc/multipath.conf allows to configure? No, I'm just considering the settings for a device that won't work at all if multipath.conf is wrong. For example, the uuid attributes, path priority, or path checker. These can't be considered configurable policies if all but one of them are invalid for a specific device type. It shouldn't even be an option to let a user select TUR path checker for NVMe, and the only checkers multipath-tools provide that even make sense for NVMe are deprecated.