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=-3.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS 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 82421C433DF for ; Thu, 20 Aug 2020 06:37:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 58A3320786 for ; Thu, 20 Aug 2020 06:37:25 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=javigon-com.20150623.gappssmtp.com header.i=@javigon-com.20150623.gappssmtp.com header.b="1oTpqa9m" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726899AbgHTGhY (ORCPT ); Thu, 20 Aug 2020 02:37:24 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58612 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725778AbgHTGhW (ORCPT ); Thu, 20 Aug 2020 02:37:22 -0400 Received: from mail-ed1-x542.google.com (mail-ed1-x542.google.com [IPv6:2a00:1450:4864:20::542]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 36E5FC061757 for ; Wed, 19 Aug 2020 23:37:22 -0700 (PDT) Received: by mail-ed1-x542.google.com with SMTP id di22so704755edb.12 for ; Wed, 19 Aug 2020 23:37:22 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=javigon-com.20150623.gappssmtp.com; s=20150623; h=from:date:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=sLKrzH9MwPqGsgXwtk2KOdG5Y1PUaWmaOENzy3RDTWI=; b=1oTpqa9mewNECohmMsYj+eRveSfefrahN/JWuEtdN5qZYeRSPgiHk+r5DSeOlqKXJ2 xHZTqWPH4bMVTL9qtKpvEdwNg9cNFu8ni1UIgCkF0UdcIgEA9Y/JZa+241+kJALWMWdd A3ilCshO5/+M08eJSNj3KoovGweA4lFzvl8yWhS7WmXTWdD/q7KhlYVAtm2N6SwLPyrp fhcLdYR2jYUoYZaUjtpUVir7zG58kru94mQ8sxSoGPDhnF4a60y1PGoAPiaDD6e6BzR+ EWrsad8bF6eimra08ezmAAp4jY5onVm5vyIIQq6jFMv0IiIE9KjkYcn4ML9mcknToqFn l1lw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:date:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=sLKrzH9MwPqGsgXwtk2KOdG5Y1PUaWmaOENzy3RDTWI=; b=dVps1A3eal7WTlcNoqHaGto6oJ6esJ9SqvdTVBc2nzQSva/gcJIig8NuyPvhUWUkNO 6piyW7fbRSv4ZdbpEQCWfeTCcGFpQPIzDC1eJ6qcgZ5+zr1b1gK+yjJJyq2cvvNJ6DBA gY3fBvQWwLqXDwHe2uAGC7Sko3rTSJHwNi/M6i8Py9BcXJpsBHxBv+2xkHhRP8ovw7cu LRar2iF9fZ8+zQRCNzghB5D/2/Fd4+CBYNMOtdwrp7FaPT8j0pEzeOmGEtLXEKGTo1Su e7QtCdpGJhWVgPA3tgfVm1JqpwSaG+DvO1/5sAk1PO7u2yZtSuj7kGwNH/G0oBhRiw9Z UxzA== X-Gm-Message-State: AOAM530Z/y16k6xIKX8AX2JKEt3CVlB4hD9Prw7aXLs8mK0aq9iSeZUo acTPZPJ6SwUES9qN1pRu8NqngQ== X-Google-Smtp-Source: ABdhPJw1f+/LS3aQnQufiPMLSgWv3ikzJM2mUKgAo9msFfUJoqiNImvZgYem58Wk3tvok8hu+xBWaw== X-Received: by 2002:aa7:d607:: with SMTP id c7mr1500254edr.184.1597905440828; Wed, 19 Aug 2020 23:37:20 -0700 (PDT) Received: from localhost ([194.62.217.57]) by smtp.gmail.com with ESMTPSA id g9sm712181edk.97.2020.08.19.23.37.19 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 19 Aug 2020 23:37:20 -0700 (PDT) From: Javier Gonzalez X-Google-Original-From: Javier Gonzalez Date: Thu, 20 Aug 2020 08:37:19 +0200 To: Jens Axboe Cc: david.fugate@linux.intel.com, Christoph Hellwig , Kanchan Joshi , "kbusch@kernel.org" , "Damien.LeMoal@wdc.com" , "sagi@grimberg.me" , "linux-nvme@lists.infradead.org" , "linux-kernel@vger.kernel.org" , "johannes.thumshirn@wdc.com" , Nitesh Shetty , SelvaKumar S Subject: Re: [PATCH 2/2] nvme: add emulation for zone-append Message-ID: <20200820063719.q6wftb23op45wigk@MacBook-Pro.localdomain> References: <20200818052936.10995-1-joshi.k@samsung.com> <20200818052936.10995-3-joshi.k@samsung.com> <20200818071249.GB2544@lst.de> <9fa64efe-8477-5d33-20ed-9619a9fe8d70@kernel.dk> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Disposition: inline In-Reply-To: <9fa64efe-8477-5d33-20ed-9619a9fe8d70@kernel.dk> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 19.08.2020 13:25, Jens Axboe wrote: >On 8/19/20 12:11 PM, David Fugate wrote: >> On Tue, 2020-08-18 at 07:12 +0000, Christoph Hellwig wrote: >>> On Tue, Aug 18, 2020 at 10:59:36AM +0530, Kanchan Joshi wrote: >>>> If drive does not support zone-append natively, enable emulation >>>> using >>>> regular write. >>>> Make emulated zone-append cmd write-lock the zone, preventing >>>> concurrent append/write on the same zone. >>> >>> I really don't think we should add this. ZNS and the Linux support >>> were all designed with Zone Append in mind, and then your company did >>> the nastiest possible move violating the normal NVMe procedures to >>> make >>> it optional. But that doesn't change the fact the Linux should keep >>> requiring it, especially with the amount of code added here and how >>> it >>> hooks in the fast path. >> >> Intel does not support making *optional* NVMe spec features *required* >> by the NVMe driver. > >It's not required, the driver will function quite fine without it. If you >want to use ZNS it's required. The Linux driver thankfully doesn't need >any vendor to sign off on what it can or cannot do, or what features >are acceptable. > >> It's forgivable WDC's accepted contribution didn't work with other >> vendors' devices choosing not to implement the optional Zone Append, >> but it's not OK to reject contributions remedying this. Provided >> there's no glaring technical issues, Samsung's contribution should be >> accepted to maintain both spec compliance as well as vendor neutrality. > >It's *always* ok to reject contributions, if those contributions cause >maintainability issues, unacceptable slowdowns, or whatever other issue >that the maintainers of said driver don't want to deal with. Any >contribution should be judged on merit, not based on political decisions >or opinions. Obviously this thread reeks of it. > I'll reply here, where the discussion diverges from this particular patch. We will stop pushing for this emulation. We have a couple of SSDs where we disabled Append, we implemented support for them, and we wanted to push the changes upstream. That's it. This is no politics not a conspiracy against the current ZNS spec. We spent a lot of time working on this spec and are actually doing a fair amount of work to support Append other places in the stack. In any case, the fuzz stops here. Javier