Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755222AbdLOLOE (ORCPT ); Fri, 15 Dec 2017 06:14:04 -0500 Received: from wolff.to ([98.103.208.27]:34776 "HELO wolff.to" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1753478AbdLOLOB (ORCPT ); Fri, 15 Dec 2017 06:14:01 -0500 Date: Fri, 15 Dec 2017 05:10:50 -0600 From: Bruno Wolff III To: weiping zhang Cc: Laura Abbott , Jan Kara , Jens Axboe , linux-mm@kvack.org, Linux Kernel Mailing List , regressions@leemhuis.info, linux-block@vger.kernel.org Subject: Re: Regression with a0747a859ef6 ("bdi: add error handle for bdi_debug_register") Message-ID: <20171215111050.GA30737@wolff.to> References: <20171214082452.GA16698@wolff.to> <20171214100927.GA26167@localhost.didichuxing.com> <20171214154136.GA12936@wolff.to> <20171215014417.GA17757@wolff.to> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.9.1 (2017-09-22) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 601 Lines: 11 On Fri, Dec 15, 2017 at 10:04:32 +0800, weiping zhang wrote: >I just want to know WARN_ON WHAT in device_add_disk, >if bdi_register_owner return error code, it may fail at any step of following: Was that output in the original boot log? I didn't see anything there that had the string WARN_ON. The first log was from a Fedora kernel. The second from a kernel I built. I used a Fedora config though. The config was probably from one of their nodebug kernels, I could build another one using a config from a debug kernel. Would that likely provide what you are looking for?