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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 C8F90C3A5A8 for ; Wed, 4 Sep 2019 17:29:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A60932087E for ; Wed, 4 Sep 2019 17:29:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731924AbfIDR3f (ORCPT ); Wed, 4 Sep 2019 13:29:35 -0400 Received: from ale.deltatee.com ([207.54.116.67]:58972 "EHLO ale.deltatee.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729020AbfIDR3f (ORCPT ); Wed, 4 Sep 2019 13:29:35 -0400 Received: from s0106ac1f6bb1ecac.cg.shawcable.net ([70.73.163.230] helo=[192.168.11.155]) by ale.deltatee.com with esmtpsa (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.89) (envelope-from ) id 1i5Z64-0008Ty-GK; Wed, 04 Sep 2019 11:29:33 -0600 To: Keith Busch Cc: Christoph Hellwig , Jens Axboe , Hannes Reinecke , Sagi Grimberg , "Martin K . Petersen" , linux-kernel@vger.kernel.org, linux-nvme@lists.infradead.org, Keith Busch References: <20190831152910.GA29439@localhost.localdomain> <33af4d94-9f6d-9baa-01fa-0f75ccee263e@deltatee.com> <20190903164620.GA20847@localhost.localdomain> <20190904060558.GA10849@lst.de> <20190904144426.GB21302@localhost.localdomain> <20190904154215.GA20422@lst.de> <20190904155445.GD21302@localhost.localdomain> <20190904163557.GF21302@localhost.localdomain> <20190904171445.GG21302@localhost.localdomain> From: Logan Gunthorpe Message-ID: <5a4cf3b0-daa2-30de-63b2-c5b28c5bb7b4@deltatee.com> Date: Wed, 4 Sep 2019 11:29:25 -0600 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.8.0 MIME-Version: 1.0 In-Reply-To: <20190904171445.GG21302@localhost.localdomain> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-SA-Exim-Connect-IP: 70.73.163.230 X-SA-Exim-Rcpt-To: keith.busch@intel.com, linux-nvme@lists.infradead.org, linux-kernel@vger.kernel.org, martin.petersen@oracle.com, sagi@grimberg.me, hare@suse.com, axboe@fb.com, hch@lst.de, kbusch@kernel.org X-SA-Exim-Mail-From: logang@deltatee.com Subject: Re: [PATCH] nvme-core: Fix subsystem instance mismatches X-SA-Exim-Version: 4.2.1 (built Tue, 02 Aug 2016 21:08:31 +0000) X-SA-Exim-Scanned: Yes (on ale.deltatee.com) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2019-09-04 11:14 a.m., Keith Busch wrote: > On Wed, Sep 04, 2019 at 11:01:22AM -0600, Logan Gunthorpe wrote: >> Oh, yes that's simpler than the struct/kref method and looks like it >> will accomplish the same thing. I did some brief testing with it and it >> seems to work for me (though I don't have any subsystems with multiple >> controllers). If you want to make a patch out of it you can add my >> >> Reviewed-by: Logan Gunthorpe > > Thanks! I'll make it a proper patch and send shortly. > > For testing multi-controller subsystems, I haven't got proper hardware > either, so I really like the nvme loop target. Here's a very simple json > defining a two namespace subsystem backed by two real nvme devices: Cool right, thanks for the tip, I should have thought of that. I just did some more loop testing with your patch and it behaves roughly as we expect. The controller and subsystem IDs never overlap unless they are created at the same time and it doesn't look like any IDs are ever leaked. With simple non-CMIC devices the ctrl and subsystem always have the same instance number. Logan