From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759248Ab0HKX7J (ORCPT ); Wed, 11 Aug 2010 19:59:09 -0400 Received: from kroah.org ([198.145.64.141]:43513 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759023Ab0HKX6v (ORCPT ); Wed, 11 Aug 2010 19:58:51 -0400 X-Mailbox-Line: From gregkh@clark.site Wed Aug 11 16:55:02 2010 Message-Id: <20100811235502.327452700@clark.site> User-Agent: quilt/0.48-11.2 Date: Wed, 11 Aug 2010 16:54:55 -0700 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org Cc: stable-review@kernel.org, torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Yan Zheng , Chris Mason , Jeff Mahoney Subject: [074/111] Btrfs: fix race between allocate and release extent buffer. In-Reply-To: <20100811235623.GA24440@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2.6.32-stable review patch. If anyone has any objections, please let us know. ------------------ From: Yan, Zheng commit f044ba7835b84e69c68b620ca8fa27e5ef67759d upstream. Increase extent buffer's reference count while holding the lock. Otherwise it can race with try_release_extent_buffer. Signed-off-by: Yan Zheng Signed-off-by: Chris Mason Acked-by: Jeff Mahoney Signed-off-by: Greg Kroah-Hartman --- fs/btrfs/extent_io.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) --- a/fs/btrfs/extent_io.c +++ b/fs/btrfs/extent_io.c @@ -3165,10 +3165,9 @@ struct extent_buffer *alloc_extent_buffe spin_unlock(&tree->buffer_lock); goto free_eb; } - spin_unlock(&tree->buffer_lock); - /* add one reference for the tree */ atomic_inc(&eb->refs); + spin_unlock(&tree->buffer_lock); return eb; free_eb: