diff --git a/kernel/cpuset.c b/kernel/cpuset.c
index e472fe139192..33eee16addb8 100644
--- a/kernel/cpuset.c
+++ b/kernel/cpuset.c
@@ -1840,8 +1840,10 @@ static void cpuset_post_clone(struct cgroup_subsys *ss,
 	cs = cgroup_cs(cgroup);
 	parent_cs = cgroup_cs(parent);
 
+	mutex_lock(&callback_mutex);
 	cs->mems_allowed = parent_cs->mems_allowed;
 	cpumask_copy(cs->cpus_allowed, parent_cs->cpus_allowed);
+	mutex_unlock(&callback_mutex);
 	return;
 }