From patchwork Tue Dec 13 19:33:33 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jeff Mahoney X-Patchwork-Id: 9473007 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 58BD560760 for ; Tue, 13 Dec 2016 19:33:43 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 669C5285D9 for ; Tue, 13 Dec 2016 19:33:43 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 59A9F28671; Tue, 13 Dec 2016 19:33:43 +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 EC683285D9 for ; Tue, 13 Dec 2016 19:33:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934921AbcLMTdk (ORCPT ); Tue, 13 Dec 2016 14:33:40 -0500 Received: from mx2.suse.de ([195.135.220.15]:52429 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933857AbcLMTdh (ORCPT ); Tue, 13 Dec 2016 14:33:37 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay1.suse.de (charybdis-ext.suse.de [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id A9184AAB9 for ; Tue, 13 Dec 2016 19:33:35 +0000 (UTC) To: linux-btrfs From: Jeff Mahoney Subject: [PATCH] btrfs: fix error handling when run_delayed_extent_op fails Message-ID: Date: Tue, 13 Dec 2016 14:33:33 -0500 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.11; rv:50.0) Gecko/20100101 Thunderbird/50.0 MIME-Version: 1.0 Content-Language: en-US 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 In __btrfs_run_delayed_refs, the error path when run_delayed_extent_op fails sets locked_ref->processing = 0 but doesn't re-increment delayed_refs->num_heads_ready. As a result, we can end up triggering the WARN_ON in btrfs_select_ref_head since the head remains in the tree with ->processing = 0 and the ready count is off. Fixes: d7df2c796d7 (Btrfs: attach delayed ref updates to delayed ref heads) Reported-by: Jon Nelson Signed-off-by: Jeff Mahoney --- fs/btrfs/extent-tree.c | 1 + 1 file changed, 1 insertion(+) diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index 4607af3..73a8d31 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -2588,6 +2588,7 @@ static noinline int __btrfs_run_delayed_refs(struct btrfs_trans_handle *trans, if (must_insert_reserved) locked_ref->must_insert_reserved = 1; locked_ref->processing = 0; + delayed_refs->num_heads_ready++; btrfs_debug(fs_info, "run_delayed_extent_op returned %d", ret);