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 X-Spam-Level: X-Spam-Status: No, score=-5.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7B451C10F25 for ; Fri, 6 Mar 2020 19:37:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4DFBE20674 for ; Fri, 6 Mar 2020 19:37:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726300AbgCFThk (ORCPT ); Fri, 6 Mar 2020 14:37:40 -0500 Received: from mx2.suse.de ([195.135.220.15]:56004 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726171AbgCFThj (ORCPT ); Fri, 6 Mar 2020 14:37:39 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id E0820AEEF; Fri, 6 Mar 2020 19:37:37 +0000 (UTC) Received: by ds.suse.cz (Postfix, from userid 10065) id 860CDDA728; Fri, 6 Mar 2020 20:37:13 +0100 (CET) Date: Fri, 6 Mar 2020 20:37:13 +0100 From: David Sterba To: madhuparnabhowmik10@gmail.com Cc: clm@fb.com, josef@toxicpanda.com, dsterba@suse.com, linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org, joel@joelfernandes.org, linux-kernel-mentees@lists.linuxfoundation.org, paulmck@kernel.org, frextrite@gmail.com, linux@roeck-us.net Subject: Re: [PATCH] fs: btrfs: block-group.c: Fix suspicious RCU usage warning Message-ID: <20200306193713.GI2902@twin.jikos.cz> Reply-To: dsterba@suse.cz Mail-Followup-To: dsterba@suse.cz, madhuparnabhowmik10@gmail.com, clm@fb.com, josef@toxicpanda.com, dsterba@suse.com, linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org, joel@joelfernandes.org, linux-kernel-mentees@lists.linuxfoundation.org, paulmck@kernel.org, frextrite@gmail.com, linux@roeck-us.net References: <20200306065243.11699-1-madhuparnabhowmik10@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200306065243.11699-1-madhuparnabhowmik10@gmail.com> User-Agent: Mutt/1.5.23.1-rc1 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Mar 06, 2020 at 12:22:43PM +0530, madhuparnabhowmik10@gmail.com wrote: > From: Madhuparna Bhowmik > > The space_info list is rcu protected. > Hence, it should be traversed with rcu_read_lock held. > > Warning: > [ 29.104591] ============================= > [ 29.104756] WARNING: suspicious RCU usage > [ 29.105046] 5.6.0-rc4-next-20200305 #1 Not tainted > [ 29.105231] ----------------------------- > [ 29.105401] fs/btrfs/block-group.c:2011 RCU-list traversed in non-reader section!! > > Reported-by: Guenter Roeck > Signed-off-by: Madhuparna Bhowmik I've updated the changelog based on comments from the mail thread and applied the patch. Thanks.