From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753523AbaCBDA3 (ORCPT ); Sat, 1 Mar 2014 22:00:29 -0500 Received: from userp1040.oracle.com ([156.151.31.81]:19277 "EHLO userp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753419AbaCBDA2 (ORCPT ); Sat, 1 Mar 2014 22:00:28 -0500 From: Sasha Levin To: tj@kernel.org, lizefan@huawei.com Cc: containers@lists.linux-foundation.org, cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, Sasha Levin Subject: [PATCH] cgroup: missing rcu read lock around task_css_set Date: Sat, 1 Mar 2014 22:00:11 -0500 Message-Id: <1393729211-937-1-git-send-email-sasha.levin@oracle.com> X-Mailer: git-send-email 1.8.3.2 X-Source-IP: acsinet21.oracle.com [141.146.126.237] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org rcu read lock should be held when calling and working with task_css_set. This patch also fixes a related lockdep warning. Signed-off-by: Sasha Levin --- kernel/cgroup.c | 2 ++ 1 files changed, 2 insertions(+), 0 deletions(-) diff --git a/kernel/cgroup.c b/kernel/cgroup.c index 8f4ddbe..f638ad6 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -4361,6 +4361,7 @@ void cgroup_exit(struct task_struct *tsk, int run_callbacks) } /* Reassign the task to the init_css_set. */ + rcu_read_lock(); cset = task_css_set(tsk); RCU_INIT_POINTER(tsk->cgroups, &init_css_set); @@ -4378,6 +4379,7 @@ void cgroup_exit(struct task_struct *tsk, int run_callbacks) if (put_cset) put_css_set(cset, true); + rcu_read_unlock(); } static void check_for_release(struct cgroup *cgrp) -- 1.7.2.5