From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wm0-f69.google.com (mail-wm0-f69.google.com [74.125.82.69]) by kanga.kvack.org (Postfix) with ESMTP id DF94C6B0038 for ; Fri, 15 Dec 2017 09:02:22 -0500 (EST) Received: by mail-wm0-f69.google.com with SMTP id v184so10341876wmf.1 for ; Fri, 15 Dec 2017 06:02:22 -0800 (PST) Received: from mail-sor-f65.google.com (mail-sor-f65.google.com. [209.85.220.65]) by mx.google.com with SMTPS id p55sor4485533edc.47.2017.12.15.06.02.20 for (Google Transport Security); Fri, 15 Dec 2017 06:02:21 -0800 (PST) MIME-Version: 1.0 In-Reply-To: <20171215111050.GA30737@wolff.to> References: <20171214082452.GA16698@wolff.to> <20171214100927.GA26167@localhost.didichuxing.com> <20171214154136.GA12936@wolff.to> <20171215014417.GA17757@wolff.to> <20171215111050.GA30737@wolff.to> From: weiping zhang Date: Fri, 15 Dec 2017 22:02:20 +0800 Message-ID: Subject: Re: Regression with a0747a859ef6 ("bdi: add error handle for bdi_debug_register") Content-Type: text/plain; charset="UTF-8" Sender: owner-linux-mm@kvack.org List-ID: To: Bruno Wolff III Cc: Laura Abbott , Jan Kara , Jens Axboe , linux-mm@kvack.org, Linux Kernel Mailing List , regressions@leemhuis.info, linux-block@vger.kernel.org 2017-12-15 19:10 GMT+08:00 Bruno Wolff III : > 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 Sorry to let you confuse, WARN_ON means we catch log as following: WARNING: CPU: 3 PID: 3486 at block/genhd.c:680 device_add_disk+0x3d9/0x460 > 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? 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. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org