X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=kernel%2Fcgroup_freezer.c;h=e5c0244962b020ab3cd4e4d00a0be04e5cc18af5;hb=10b06122afcc78468bd1d009633cb71e528acdc5;hp=da5e139755319aa9a554a57ac699470144dcf055;hpb=2f4084209adc77f9a1c9f38db3019a509e167882;p=firefly-linux-kernel-4.4.55.git

diff --git a/kernel/cgroup_freezer.c b/kernel/cgroup_freezer.c
index da5e13975531..e5c0244962b0 100644
--- a/kernel/cgroup_freezer.c
+++ b/kernel/cgroup_freezer.c
@@ -205,9 +205,12 @@ static void freezer_fork(struct cgroup_subsys *ss, struct task_struct *task)
 	 * No lock is needed, since the task isn't on tasklist yet,
 	 * so it can't be moved to another cgroup, which means the
 	 * freezer won't be removed and will be valid during this
-	 * function call.
+	 * function call.  Nevertheless, apply RCU read-side critical
+	 * section to suppress RCU lockdep false positives.
 	 */
+	rcu_read_lock();
 	freezer = task_freezer(task);
+	rcu_read_unlock();
 
 	/*
 	 * The root cgroup is non-freezable, so we can skip the