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 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7774DC433EF for ; Wed, 23 Feb 2022 03:30:30 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id EB65C8D0002; Tue, 22 Feb 2022 22:30:29 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id E65EA8D0001; Tue, 22 Feb 2022 22:30:29 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id D2E2E8D0002; Tue, 22 Feb 2022 22:30:29 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0135.hostedemail.com [216.40.44.135]) by kanga.kvack.org (Postfix) with ESMTP id C3B478D0001 for ; Tue, 22 Feb 2022 22:30:29 -0500 (EST) Received: from smtpin28.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id 671E18249980 for ; Wed, 23 Feb 2022 03:30:29 +0000 (UTC) X-FDA: 79172616978.28.DD342F4 Received: from lgeamrelo11.lge.com (lgeamrelo11.lge.com [156.147.23.51]) by imf03.hostedemail.com (Postfix) with ESMTP id 8CD8720005 for ; Wed, 23 Feb 2022 03:30:27 +0000 (UTC) Received: from unknown (HELO lgeamrelo01.lge.com) (156.147.1.125) by 156.147.23.51 with ESMTP; 23 Feb 2022 12:30:24 +0900 X-Original-SENDERIP: 156.147.1.125 X-Original-MAILFROM: byungchul.park@lge.com Received: from unknown (HELO X58A-UD3R) (10.177.244.38) by 156.147.1.125 with ESMTP; 23 Feb 2022 12:30:24 +0900 X-Original-SENDERIP: 10.177.244.38 X-Original-MAILFROM: byungchul.park@lge.com Date: Wed, 23 Feb 2022 12:30:12 +0900 From: Byungchul Park To: Jan Kara Cc: torvalds@linux-foundation.org, damien.lemoal@opensource.wdc.com, linux-ide@vger.kernel.org, adilger.kernel@dilger.ca, linux-ext4@vger.kernel.org, mingo@redhat.com, linux-kernel@vger.kernel.org, peterz@infradead.org, will@kernel.org, tglx@linutronix.de, rostedt@goodmis.org, joel@joelfernandes.org, sashal@kernel.org, daniel.vetter@ffwll.ch, chris@chris-wilson.co.uk, duyuyang@gmail.com, johannes.berg@intel.com, tj@kernel.org, tytso@mit.edu, willy@infradead.org, david@fromorbit.com, amir73il@gmail.com, bfields@fieldses.org, gregkh@linuxfoundation.org, kernel-team@lge.com, linux-mm@kvack.org, akpm@linux-foundation.org, mhocko@kernel.org, minchan@kernel.org, hannes@cmpxchg.org, vdavydov.dev@gmail.com, sj@kernel.org, jglisse@redhat.com, dennis@kernel.org, cl@linux.com, penberg@kernel.org, rientjes@google.com, vbabka@suse.cz, ngupta@vflare.org, linux-block@vger.kernel.org, axboe@kernel.dk, paolo.valente@linaro.org, josef@toxicpanda.com, linux-fsdevel@vger.kernel.org, viro@zeniv.linux.org.uk, jack@suse.com, jlayton@kernel.org, dan.j.williams@intel.com, hch@infradead.org, djwong@kernel.org, dri-devel@lists.freedesktop.org, airlied@linux.ie, rodrigosiqueiramelo@gmail.com, melissa.srw@gmail.com, hamohammed.sa@gmail.com Subject: Re: Report 1 in ext4 and journal based on v5.17-rc1 Message-ID: <20220223033012.GC26277@X58A-UD3R> References: <1645095472-26530-1-git-send-email-byungchul.park@lge.com> <1645096204-31670-1-git-send-email-byungchul.park@lge.com> <20220222082723.rddf4typah3wegrc@quack3.lan> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220222082723.rddf4typah3wegrc@quack3.lan> User-Agent: Mutt/1.5.21 (2010-09-15) X-Rspamd-Queue-Id: 8CD8720005 X-Stat-Signature: t4b9wa63tkn4ai5duwuuqz8y9r3ycwdo X-Rspam-User: Authentication-Results: imf03.hostedemail.com; dkim=none; spf=pass (imf03.hostedemail.com: domain of byungchul.park@lge.com designates 156.147.23.51 as permitted sender) smtp.mailfrom=byungchul.park@lge.com; dmarc=none X-Rspamd-Server: rspam05 X-HE-Tag: 1645587027-138204 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Tue, Feb 22, 2022 at 09:27:23AM +0100, Jan Kara wrote: > On Thu 17-02-22 20:10:03, Byungchul Park wrote: > > [ 7.009608] =================================================== > > [ 7.009613] DEPT: Circular dependency has been detected. > > [ 7.009614] 5.17.0-rc1-00014-g8a599299c0cb-dirty #30 Tainted: G W > > [ 7.009616] --------------------------------------------------- > > [ 7.009617] summary > > [ 7.009618] --------------------------------------------------- > > [ 7.009618] *** DEADLOCK *** > > [ 7.009618] > > [ 7.009619] context A > > [ 7.009619] [S] (unknown)(&(bit_wait_table + i)->dmap:0) > > [ 7.009621] [W] down_write(&ei->i_data_sem:0) > > [ 7.009623] [E] event(&(bit_wait_table + i)->dmap:0) > > [ 7.009624] > > [ 7.009625] context B > > [ 7.009625] [S] down_read(&ei->i_data_sem:0) > > [ 7.009626] [W] wait(&(bit_wait_table + i)->dmap:0) > > [ 7.009627] [E] up_read(&ei->i_data_sem:0) > > [ 7.009628] > > Looking into this I have noticed that Dept here tracks bitlocks (buffer > locks in particular) but it apparently treats locks on all buffers as one > locking class so it conflates lock on superblock buffer with a lock on > extent tree block buffer. These are wastly different locks with different > locking constraints. So to avoid false positives in filesystems we will > need to add annotations to differentiate locks on different buffers (based > on what the block is used for). Similarly how we e.g. annotate i_rwsem for > different inodes. Hi Jan Kara, I just understood why some guys in this space got mad at Dept reports. I barely got reports from the lock you mentioned with my system - precisely speaking only one, even though I've been rebooting my system many times. But another report that someone gave for me showed there were a lot of reports from the lock. Your comment and the report are so much helpful. I need to assign each's own class first for the buffer locks. Thank you very much. Thanks, Byungchul > > Honza > -- > Jan Kara > SUSE Labs, CR