Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754646AbYJUAtS (ORCPT ); Mon, 20 Oct 2008 20:49:18 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751968AbYJUAtI (ORCPT ); Mon, 20 Oct 2008 20:49:08 -0400 Received: from cn.fujitsu.com ([222.73.24.84]:60090 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1751291AbYJUAtG (ORCPT ); Mon, 20 Oct 2008 20:49:06 -0400 Message-ID: <48FD26F5.1070809@cn.fujitsu.com> Date: Tue, 21 Oct 2008 08:48:53 +0800 From: Li Zefan User-Agent: Thunderbird 2.0.0.9 (X11/20071115) MIME-Version: 1.0 To: Andrew Morton CC: Matt Helsley , Cedric Le Goater , LKML , Linux Containers Subject: [PATCH 1/4] freezer_cg: fix improper BUG_ON() causing oops Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1143 Lines: 32 The BUG_ON() should be protected by freezer->lock, otherwise it can be triggered easily when a task has been unfreezed but the corresponding cgroup hasn't been changed to FROZEN state. Signed-off-by: Li Zefan --- kernel/cgroup_freezer.c | 3 ++- 1 files changed, 2 insertions(+), 1 deletions(-) diff --git a/kernel/cgroup_freezer.c b/kernel/cgroup_freezer.c index e950569..7f54d1c 100644 --- a/kernel/cgroup_freezer.c +++ b/kernel/cgroup_freezer.c @@ -190,8 +190,9 @@ static void freezer_fork(struct cgroup_subsys *ss, struct task_struct *task) freezer = task_freezer(task); task_unlock(task); - BUG_ON(freezer->state == CGROUP_FROZEN); spin_lock_irq(&freezer->lock); + BUG_ON(freezer->state == CGROUP_FROZEN); + /* Locking avoids race with FREEZING -> THAWED transitions. */ if (freezer->state == CGROUP_FREEZING) freeze_task(task, true); -- 1.5.4.rc3 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/