From patchwork Fri Nov 3 08:28:05 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lu Fengqi X-Patchwork-Id: 10039635 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 40AEA600C5 for ; Fri, 3 Nov 2017 08:29:05 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 2F4DB2953C for ; Fri, 3 Nov 2017 08:29:05 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 240662953E; Fri, 3 Nov 2017 08:29:05 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id BD1092953C for ; Fri, 3 Nov 2017 08:29:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755818AbdKCI3B (ORCPT ); Fri, 3 Nov 2017 04:29:01 -0400 Received: from mail.cn.fujitsu.com ([183.91.158.132]:46305 "EHLO heian.cn.fujitsu.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1755801AbdKCI26 (ORCPT ); Fri, 3 Nov 2017 04:28:58 -0400 X-IronPort-AV: E=Sophos;i="5.43,368,1503331200"; d="scan'208";a="29870831" Received: from localhost (HELO cn.fujitsu.com) ([10.167.33.5]) by heian.cn.fujitsu.com with ESMTP; 03 Nov 2017 16:28:48 +0800 Received: from G08CNEXCHPEKD01.g08.fujitsu.local (unknown [10.167.33.80]) by cn.fujitsu.com (Postfix) with ESMTP id E3C0448089DC for ; Fri, 3 Nov 2017 16:28:49 +0800 (CST) Received: from localhost.localdomain (10.167.226.155) by G08CNEXCHPEKD01.g08.fujitsu.local (10.167.33.89) with Microsoft SMTP Server (TLS) id 14.3.361.1; Fri, 3 Nov 2017 16:28:49 +0800 From: Lu Fengqi To: Subject: [PATCH RESEND 3/4] btrfs-progs: lowmem check: Fix false alert about referencer count mismatch Date: Fri, 3 Nov 2017 16:28:05 +0800 Message-ID: <20171103082806.22448-4-lufq.fnst@cn.fujitsu.com> X-Mailer: git-send-email 2.15.0 In-Reply-To: <20171103082806.22448-1-lufq.fnst@cn.fujitsu.com> References: <20171103082806.22448-1-lufq.fnst@cn.fujitsu.com> MIME-Version: 1.0 X-Originating-IP: [10.167.226.155] X-yoursite-MailScanner-ID: E3C0448089DC.AE295 X-yoursite-MailScanner: Found to be clean X-yoursite-MailScanner-From: lufq.fnst@cn.fujitsu.com Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP The normal back reference counting doesn't care about the extent referred by the extent data in the shared leaf. The check_extent_data_backref function need to skip the leaf that owner mismatch with the root_id. Reported-by: Marc MERLIN Signed-off-by: Lu Fengqi --- cmds-check.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/cmds-check.c b/cmds-check.c index 5750bb72..a93ac2c8 100644 --- a/cmds-check.c +++ b/cmds-check.c @@ -12468,7 +12468,8 @@ static int check_extent_data_backref(struct btrfs_fs_info *fs_info, leaf = path.nodes[0]; slot = path.slots[0]; - if (slot >= btrfs_header_nritems(leaf)) + if (slot >= btrfs_header_nritems(leaf) || + btrfs_header_owner(leaf) != root_id) goto next; btrfs_item_key_to_cpu(leaf, &key, slot); if (key.objectid != objectid || key.type != BTRFS_EXTENT_DATA_KEY)