Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752705AbdLUPiy (ORCPT ); Thu, 21 Dec 2017 10:38:54 -0500 Received: from wolff.to ([98.103.208.27]:41204 "HELO wolff.to" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1752118AbdLUPiv (ORCPT ); Thu, 21 Dec 2017 10:38:51 -0500 Date: Thu, 21 Dec 2017 09:36:31 -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, weiping zhang , linux-block@vger.kernel.org Subject: Re: Regression with a0747a859ef6 ("bdi: add error handle for bdi_debug_register") Message-ID: <20171221153631.GA2300@wolff.to> References: <20171221130057.GA26743@wolff.to> <20171221151843.GA453@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: 712 Lines: 14 On Thu, Dec 21, 2017 at 23:31:40 +0800, weiping zhang wrote: >does every time boot fail can trigger WANRING in device_add_disk ? Not that I see. But the message could scroll off the screen. The boot gets far enough that systemd copies over dmesg output to permanent storage that I can see on my next successful boot. That's where I looked for the warning output you want. I never saw it for any kernels I compiled myself. Only when I test kernels built by Fedora do I see it. I just tried booting to single user and the boot still hangs. When I build the kernels, the compiler options are probably a bit different than when Fedora does. That might affect what happens during boot.