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 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 5E166C433F5 for ; Mon, 14 Feb 2022 08:13:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=LTxTHVGH4NrPNv4Bdg7lSoqdD/RrbvE8+KFKBZNB3qo=; b=t60zQopot1swyuXWggC5uLrYRk XCAw8emSbQEsW5vfy/v13eGOu8U7VD1aiDUv2bxMGcP9fB8ne/2OAOxLQyR7pVVmt5JBpVLRynvfz TQ9TPiIXvL2WWRpLrNPK+1KWi54IBffAV2S7xXIHHTHIbprVjmldFHHYC5jWJlSNbm/CrETBrC5h3 fRMnZLiO9H116zMF2vVgGUl0lsKIr2aRTCH9lat6D+yQ1d5bXK2cwbYUCgHTGO9T7IpPgY0ycPf9Z No4abnb6Pwz/Z9oi3fGBhF9UEDoUyDfZzz1D9Y/NgZ3KUKrd9W8OyQOgjZoRKLxMuoB0nle/qMFX4 XuVqUH2Q==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1nJWTw-00DoUy-3X; Mon, 14 Feb 2022 08:13:12 +0000 Received: from verein.lst.de ([213.95.11.211]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1nJWTk-00DoU6-AO for linux-nvme@lists.infradead.org; Mon, 14 Feb 2022 08:13:01 +0000 Received: by verein.lst.de (Postfix, from userid 2407) id D132D68AA6; Mon, 14 Feb 2022 09:12:52 +0100 (CET) Date: Mon, 14 Feb 2022 09:12:52 +0100 From: Christoph Hellwig To: Keith Busch Cc: Christoph Hellwig , Uday Shankar , linux-nvme@lists.infradead.org, Prabhath Sajeepa , Jens Axboe , Sagi Grimberg Subject: Re: Native multipath across multiple subsystem NQNs Message-ID: <20220214081252.GA18231@lst.de> References: <20220211220714.GA370236@dev-ushankar.dev.purestorage.com> <20220212063422.GA16561@lst.de> <20220212212221.GB1660900@dhcp-10-100-145-180.wdc.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220212212221.GB1660900@dhcp-10-100-145-180.wdc.com> User-Agent: Mutt/1.5.17 (2007-11-01) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220214_001300_548427_EB497E3E X-CRM114-Status: GOOD ( 16.67 ) X-BeenThere: linux-nvme@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "Linux-nvme" Errors-To: linux-nvme-bounces+linux-nvme=archiver.kernel.org@lists.infradead.org On Sat, Feb 12, 2022 at 01:22:21PM -0800, Keith Busch wrote: > On Sat, Feb 12, 2022 at 07:34:22AM +0100, Christoph Hellwig wrote: > > The answer is neither. The fact that NVMe with ANA required namespaces > > to be be attached to the same subsystem is good and important. > > TPE 4034 is retrograde and completely broken in this respect and should > > have never been ratifier. Please fix your storage system to export > > virtual subsystems like everyone else and don't break the nice NVMe > > architecture. > > If anything, the driver could check for duplicate namespace identifiers > across subsystems so that we could warn about or prevent exposing them. Yes, this has actually been something I've been wanting to do for a long time.