From: Greg KH Subject: [patch 098/104] ext4: add checksum calculation when clearing UNINIT flag in ext4_new_inode Date: Wed, 3 Dec 2008 11:56:46 -0800 Message-ID: <20081203195646.GU8950@kroah.com> References: <20081203193901.715896543@mini.kroah.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Justin Forbes , Zwane Mwaikambo , Theodore Ts'o , Randy Dunlap , Dave Jones , Chuck Wolber , Chris Wedgwood , Michael Krufky , Chuck Ebbert , Domenico Andreoli , Willy Tarreau , Rodrigo Rubira Branco , Jake Edge , Eugene Teo , torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Frederic Bohe , Ext4 Developers List To: linux-kernel@vger.kernel.org, stable@kernel.org Return-path: Received: from kroah.org ([198.145.64.141]:56795 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752709AbYLCT6F (ORCPT ); Wed, 3 Dec 2008 14:58:05 -0500 Content-Disposition: inline; filename="ext4-add-checksum-calculation-when-clearing-uninit-flag-in-ext4_new_inode.patch" In-Reply-To: <20081203194725.GA8950@kroah.com> Sender: linux-ext4-owner@vger.kernel.org List-ID: 2.6.27-stable review patch. If anyone has any objections, please let us know. ------------------ From: Frederic Bohe (cherry picked from commit 23712a9c28b9f80a8cf70c8490358d5f562d2465) When initializing an uninitialized block group in ext4_new_inode(), its block group checksum must be re-calculated. This fixes a race when several threads try to allocate a new inode in an UNINIT'd group. There is some question whether we need to be initializing the block bitmap in ext4_new_inode() at all, but for now, if we are going to init the block group, let's eliminate the race. Signed-off-by: Frederic Bohe Signed-off-by: "Theodore Ts'o" Signed-off-by: Greg Kroah-Hartman --- fs/ext4/ialloc.c | 2 ++ 1 file changed, 2 insertions(+) --- a/fs/ext4/ialloc.c +++ b/fs/ext4/ialloc.c @@ -717,6 +717,8 @@ got: gdp->bg_flags &= cpu_to_le16(~EXT4_BG_BLOCK_UNINIT); free = ext4_free_blocks_after_init(sb, group, gdp); gdp->bg_free_blocks_count = cpu_to_le16(free); + gdp->bg_checksum = ext4_group_desc_csum(sbi, group, + gdp); } spin_unlock(sb_bgl_lock(sbi, group));