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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id EECF1C433EF for ; Tue, 15 Mar 2022 08:46:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1346176AbiCOIr2 (ORCPT ); Tue, 15 Mar 2022 04:47:28 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59372 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1345984AbiCOIrZ (ORCPT ); Tue, 15 Mar 2022 04:47:25 -0400 Received: from verein.lst.de (verein.lst.de [213.95.11.211]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 412024D24A for ; Tue, 15 Mar 2022 01:46:14 -0700 (PDT) Received: by verein.lst.de (Postfix, from userid 2407) id 5183D68AA6; Tue, 15 Mar 2022 09:46:11 +0100 (CET) Date: Tue, 15 Mar 2022 09:46:11 +0100 From: "hch@lst.de" To: Sagi Grimberg Cc: "hch@lst.de" , Sungup Moon , "kbusch@kernel.org" , "axboe@fb.com" , "linux-nvme@lists.infradead.org" , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH v2] driver/nvme/host: Support duplicated nsid for the private ns Message-ID: <20220315084611.GA3961@lst.de> References: <20220314110545epcms2p4a227eac7c4652445050e70ee2350635d@epcms2p4> <20220315071230.GA2069@lst.de> <20220315071926.GA2137@lst.de> <20220315084035.GA3834@lst.de> <6ac83f8b-01e6-5394-0570-023ac6b1a71d@grimberg.me> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <6ac83f8b-01e6-5394-0570-023ac6b1a71d@grimberg.me> User-Agent: Mutt/1.5.17 (2007-11-01) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Mar 15, 2022 at 10:42:56AM +0200, Sagi Grimberg wrote: >>>> + * We also do this for private namespaces as the namespace sharing flag >>>> + * could change after a rescan. >>> >>> What happens in this case? we now have non-unique shared namespaces? >> >> The non-uniqueue NSIDs can only happen for private namespaces. > > But what happens if this changes upon a rescan as you commented? Well, it can't change to shared as the nsids are non-unique. If we want to be paranoid we could add a sanity check for that, but then again there are a bunch of other things where we could be more paranoid.