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=-8.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 autolearn=ham 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 19728C433E1 for ; Thu, 27 Aug 2020 11:35:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E2F3C22CB1 for ; Thu, 27 Aug 2020 11:35:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728736AbgH0LeB (ORCPT ); Thu, 27 Aug 2020 07:34:01 -0400 Received: from mx2.suse.de ([195.135.220.15]:42410 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728731AbgH0LdR (ORCPT ); Thu, 27 Aug 2020 07:33:17 -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 DC12AAE17; Thu, 27 Aug 2020 11:33:48 +0000 (UTC) Received: by ds.suse.cz (Postfix, from userid 10065) id BFAA5DA703; Thu, 27 Aug 2020 13:32:07 +0200 (CEST) Date: Thu, 27 Aug 2020 13:32:07 +0200 From: David Sterba To: Qu Wenruo Cc: linux-btrfs@vger.kernel.org Subject: Re: [PATCH 1/2] btrfs: qgroup: fix wrong qgroup metadata reserve for delayed inode Message-ID: <20200827113207.GL28318@twin.jikos.cz> Reply-To: dsterba@suse.cz Mail-Followup-To: dsterba@suse.cz, Qu Wenruo , linux-btrfs@vger.kernel.org References: <20200724064610.69442-1-wqu@suse.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200724064610.69442-1-wqu@suse.com> 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, Jul 24, 2020 at 02:46:09PM +0800, Qu Wenruo wrote: > For delayed inode facility, qgroup metadata is reserved for it, and > later freed. > > However we're freeing more bytes than we reserved. > In btrfs_delayed_inode_reserve_metadata(): > > num_bytes = btrfs_calc_metadata_size(fs_info, 1); > ... > ret = btrfs_qgroup_reserve_meta_prealloc(root, > fs_info->nodesize, true); > ... > if (!ret) { > node->bytes_reserved = num_bytes; > > But in btrfs_delayed_inode_release_metadata(): > > if (qgroup_free) > btrfs_qgroup_free_meta_prealloc(node->root, > node->bytes_reserved); > else > btrfs_qgroup_convert_reserved_meta(node->root, > node->bytes_reserved); > > This means, we're always releasing more qgroup metadata rsv than we have > reserved. > > This won't trigger selftest warning, as btrfs qgroup metadata rsv has > extra protection against cases like quota enabled half-way. > > But we still need to fix this problem any way. > > This patch will use the same num_bytes for qgroup metadata rsv so we > could handle it correctly. > > Fixes: f218ea6c4792 ("btrfs: delayed-inode: Remove wrong qgroup meta reservation calls") > Signed-off-by: Qu Wenruo Added to misc-next. Patch 2/2 should go to stable (4.19+) but it does not apply even to 5.8 due to some other intermediate changes. I have tagged it for 4.19 but it will expectedly fail to apply. A backport would be needed then.