Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755561AbdLORTD (ORCPT ); Fri, 15 Dec 2017 12:19:03 -0500 Received: from mail-oi0-f42.google.com ([209.85.218.42]:41807 "EHLO mail-oi0-f42.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755361AbdLORTA (ORCPT ); Fri, 15 Dec 2017 12:19:00 -0500 X-Google-Smtp-Source: ACJfBou+9V0rLpzSc9iKxgSTnL5G0l8VZ1l406xiLTXZYGgprMe13dzZfsGaU/ENuUVzDrRnywqknw== Subject: Re: Regression with a0747a859ef6 ("bdi: add error handle for bdi_debug_register") To: Bruno Wolff III , weiping zhang Cc: Jan Kara , Jens Axboe , linux-mm@kvack.org, Linux Kernel Mailing List , regressions@leemhuis.info, linux-block@vger.kernel.org References: <20171214082452.GA16698@wolff.to> <20171214100927.GA26167@localhost.didichuxing.com> <20171214154136.GA12936@wolff.to> <20171215014417.GA17757@wolff.to> <20171215111050.GA30737@wolff.to> <20171215163048.GA15928@wolff.to> From: Laura Abbott Message-ID: <533198ad-b756-3e0a-c3bd-9aae0a42d170@redhat.com> Date: Fri, 15 Dec 2017 09:18:56 -0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.5.0 MIME-Version: 1.0 In-Reply-To: <20171215163048.GA15928@wolff.to> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1238 Lines: 14 On 12/15/2017 08:30 AM, Bruno Wolff III wrote: > On Fri, Dec 15, 2017 at 22:02:20 +0800, >  weiping zhang wrote: >> >> Yes, please help reproduce this issue include my debug patch. Reproduce means >> we can see WARN_ON in device_add_disk caused by failure of bdi_register_owner. > > I'm not sure why yet, but I'm only getting the warning message you want with Fedora kernels, not the ones I am building (with or without your test patch). I'll attach a debug config file if you want to look there. But in theory that should be essentially what Fedora is using for theirs. They probably have some out of tree patches they are applying, but I wouldn't expect those to make a difference here. I think they now have a tree somewhere that I can try to build from that has their patches applied to the upstream kernel and if I can find it I will try building it just to test this out. > > I only have about 6 hours of physical access to the machine exhibiting the problem, and after that I won't be able to do test boots until Monday. You can see the trees Fedora produces at https://git.kernel.org/pub/scm/linux/kernel/git/jwboyer/fedora.git which includes the configs (you want to look at the ones withtout - debug)