diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h
index 76f4265efee9..3e270822b915 100644
--- a/include/linux/perf_event.h
+++ b/include/linux/perf_event.h
@@ -1347,6 +1347,9 @@ static inline void perf_sample_save_brstack(struct perf_sample_data *data,
 
 	if (branch_sample_hw_index(event))
 		size += sizeof(u64);
+
+	brs->nr = min_t(u16, event->attr.sample_max_stack, brs->nr);
+
 	size += brs->nr * sizeof(struct perf_branch_entry);
 
 	/*
diff --git a/include/uapi/linux/perf_event.h b/include/uapi/linux/perf_event.h
index 0524d541d4e3..5fc753c23734 100644
--- a/include/uapi/linux/perf_event.h
+++ b/include/uapi/linux/perf_event.h
@@ -385,6 +385,8 @@ enum perf_event_read_format {
  *
  * @sample_max_stack: Max number of frame pointers in a callchain,
  *		      should be < /proc/sys/kernel/perf_event_max_stack
+ *		      Max number of entries of branch stack
+ *		      should be < hardware limit
  */
 struct perf_event_attr {