diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index 5c6dd7ed26a7..cbb6314f1836 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -5616,8 +5616,14 @@ struct cgroup_subsys_state *css_lookup(struct cgroup_subsys *ss, int id)
 }
 EXPORT_SYMBOL_GPL(css_lookup);
 
-/*
- * get corresponding css from file open on cgroupfs directory
+/**
+ * cgroup_css_from_dir - get corresponding css from file open on cgroup dir
+ * @f: directory file of interest
+ * @id: subsystem id of interest
+ *
+ * Must be called under RCU read lock.  The caller is responsible for
+ * pinning the returned css if it needs to be accessed outside the RCU
+ * critical section.
  */
 struct cgroup_subsys_state *cgroup_css_from_dir(struct file *f, int id)
 {
@@ -5625,6 +5631,8 @@ struct cgroup_subsys_state *cgroup_css_from_dir(struct file *f, int id)
 	struct inode *inode;
 	struct cgroup_subsys_state *css;
 
+	WARN_ON_ONCE(!rcu_read_lock_held());
+
 	inode = file_inode(f);
 	/* check in cgroup filesystem dir */
 	if (inode->i_op != &cgroup_dir_inode_operations)
diff --git a/kernel/events/core.c b/kernel/events/core.c
index c199c4f24910..23261f957713 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -591,6 +591,8 @@ static inline int perf_cgroup_connect(int fd, struct perf_event *event,
 	if (!f.file)
 		return -EBADF;
 
+	rcu_read_lock();
+
 	css = cgroup_css_from_dir(f.file, perf_subsys_id);
 	if (IS_ERR(css)) {
 		ret = PTR_ERR(css);
@@ -617,6 +619,7 @@ static inline int perf_cgroup_connect(int fd, struct perf_event *event,
 		ret = -EINVAL;
 	}
 out:
+	rcu_read_unlock();
 	fdput(f);
 	return ret;
 }