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=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=no 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 838A2C433E2 for ; Mon, 7 Sep 2020 13:11:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 56D5420768 for ; Mon, 7 Sep 2020 13:11:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729278AbgIGNHo (ORCPT ); Mon, 7 Sep 2020 09:07:44 -0400 Received: from mx2.suse.de ([195.135.220.15]:42624 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729318AbgIGNGi (ORCPT ); Mon, 7 Sep 2020 09:06:38 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 976F7AC65; Mon, 7 Sep 2020 13:06:37 +0000 (UTC) Received: by ds.suse.cz (Postfix, from userid 10065) id 77132DA7C8; Mon, 7 Sep 2020 15:05:22 +0200 (CEST) Date: Mon, 7 Sep 2020 15:05:22 +0200 From: David Sterba To: dsterba@suse.cz, Josef Bacik , linux-btrfs@vger.kernel.org, kernel-team@fb.com Subject: Re: [PATCH 0/4][v2] Lockdep fixes Message-ID: <20200907130522.GB28318@twin.jikos.cz> Reply-To: dsterba@suse.cz Mail-Followup-To: dsterba@suse.cz, Josef Bacik , linux-btrfs@vger.kernel.org, kernel-team@fb.com References: <20200904142000.GX28318@twin.jikos.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200904142000.GX28318@twin.jikos.cz> User-Agent: Mutt/1.5.23.1-rc1 (2014-03-12) Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org On Fri, Sep 04, 2020 at 04:20:00PM +0200, David Sterba wrote: > On Tue, Sep 01, 2020 at 05:40:34PM -0400, Josef Bacik wrote: > > v1->v2: > > - Included the add_missing_dev patch in the series. > > - Added a patch to kill the rcu protection for fs_info->space_info. > > - Fixed the raid sysfs init stuff to be completely out of link_block_group, as > > it causes a lockdep splat with the rwsem conversion. > > > > Hello, > > > > These are the last two lockdep splats I'm able to see in my testing. We have > > like 4 variations of the same lockdep splat that's addressed by > > > > btrfs: do not create raid sysfs entries under chunk_mutex > > > > Basically this particular dependency pulls in the kernfs_mutex under the > > chunk_mutex, and so we have like 4 issues in github with slightly different > > splats, but are all fixed by that fix. With these two patches (and the one I > > sent the other day for add_missing_dev) I haven't hit any lockdep splats in 6 > > runs of xfstests on 3 different VMs in the last 12 hours. That means it should > > take Dave at least 2 runs before he hits a new one. Thanks, > > > > Josef Bacik (4): > > btrfs: fix lockdep splat in add_missing_dev > > btrfs: init sysfs for devices outside of the chunk_mutex > > So the two patches were in misc-next and I started to see lockdep > complaining in btrfs/011, which is very early in the test list and this > makes it impossible to notice further lockdep reports. So it was really because of the rwsem switch in for-next. Misc-next passes without lockdep warnings up to btrfs/124, which is the kernfs/fs_reclaim case and there's a patch for that. > I'll move the patches to a topic branch and will retest misc-next to see > what's the actual list of lockdep things to fix, so we have a clean > state before the eb rwsem switch. The patches are in misc-next and I'll add more once I test them.