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=-2.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,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 13EA6C433E0 for ; Wed, 3 Jun 2020 16:23:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EA89420679 for ; Wed, 3 Jun 2020 16:23:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726099AbgFCQXm (ORCPT ); Wed, 3 Jun 2020 12:23:42 -0400 Received: from verein.lst.de ([213.95.11.211]:51390 "EHLO verein.lst.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726095AbgFCQXm (ORCPT ); Wed, 3 Jun 2020 12:23:42 -0400 Received: by verein.lst.de (Postfix, from userid 2407) id 11D4168B05; Wed, 3 Jun 2020 18:23:39 +0200 (CEST) Date: Wed, 3 Jun 2020 18:23:38 +0200 From: Christoph Hellwig To: Dakshaja Uppalapati Cc: Christoph Hellwig , eduard@hasenleithner.at, kbusch@kernel.org, sagi@grimberg.me, gregkh@linuxfoundation.org, nirranjan@chelsio.com, bharat@chelsio.com, stable@vger.kernel.org Subject: Re: [PATCH nvme] nvme: Revert "nvme: Discard workaround for non-conformant devices" Message-ID: <20200603162338.GA27240@lst.de> References: <20200603091851.16957-1-dakshaja@chelsio.com> <20200603130750.GA13511@lst.de> <20200603161717.GA11442@chelsio.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200603161717.GA11442@chelsio.com> User-Agent: Mutt/1.5.17 (2007-11-01) Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org On Wed, Jun 03, 2020 at 09:47:18PM +0530, Dakshaja Uppalapati wrote: > > Err, why? Please send an actual bug report with details of your > > setup. > > Hi Christoph, > > Here is the link describing the issue initially reported for upstream > kernel 5.5: > > https://lore.kernel.org/linux-nvme/CH2PR12MB40053A64681EFA3E6F63FDFBDD2A0@CH2PR12MB4005.namprd12.prod.outlook.com/ > > Issue is later fixed with upstream commit b716e688. We are talking about two different things here. One is the Linux NVMe host code that can be used with lots of different controllers. Many of them are PCIe controller, especially cheap ones. The other is the Linux NVMe target code. So if a fix for very common PCIe controller trigger a bug in the target code there is no 1:1 relationship as even if you are talking to a Linux fabrics controller it usually runs a different kernel version on a different system. That being said you can always backport that fix as well, which probably is a good idea as it fixes a real bug. Nevermind that nothing in your revert patch indicated it wasn't for mainline.