From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1946848Ab2ERXIx (ORCPT ); Fri, 18 May 2012 19:08:53 -0400 Received: from mail-pz0-f46.google.com ([209.85.210.46]:53122 "EHLO mail-pz0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1946652Ab2ERXHn (ORCPT ); Fri, 18 May 2012 19:07:43 -0400 Message-Id: <20120518212652.491290217@linuxfoundation.org> User-Agent: quilt/0.60-19.1 Date: Fri, 18 May 2012 14:27:25 -0700 From: Greg KH To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Sha Zhengju , KAMEZAWA Hiroyuki , "Kirill A. Shutemov" Subject: [ 36/47] memcg: free spare array to avoid memory leak In-Reply-To: <20120518212701.GA5023@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.3-stable review patch. If anyone has any objections, please let me know. ------------------ From: Sha Zhengju commit 8c7577637ca31385e92769a77e2ab5b428e8b99c upstream. When the last event is unregistered, there is no need to keep the spare array anymore. So free it to avoid memory leak. Signed-off-by: Sha Zhengju Acked-by: KAMEZAWA Hiroyuki Reviewed-by: Kirill A. Shutemov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- mm/memcontrol.c | 6 ++++++ 1 file changed, 6 insertions(+) --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -4480,6 +4480,12 @@ static void mem_cgroup_usage_unregister_ swap_buffers: /* Swap primary and spare array */ thresholds->spare = thresholds->primary; + /* If all events are unregistered, free the spare array */ + if (!new) { + kfree(thresholds->spare); + thresholds->spare = NULL; + } + rcu_assign_pointer(thresholds->primary, new); /* To be sure that nobody uses thresholds */