diff --git a/Documentation/admin-guide/cgroup-v2.rst b/Documentation/admin-guide/cgroup-v2.rst
index 7ce60fefc7ad..14b8c571c0d1 100644
--- a/Documentation/admin-guide/cgroup-v2.rst
+++ b/Documentation/admin-guide/cgroup-v2.rst
@@ -2257,10 +2257,11 @@ groups D and F will influence each other.  Group G will influence nobody::
 So the ideal way to configure this is to set io.latency in groups A, B, and C.
 Generally you do not want to set a value lower than the latency your device
 supports.  Experiment to find the value that works best for your workload.
-Start at higher than the expected latency for your device and watch the
-avg_lat value in io.stat for your workload group to get an idea of the
-latency you see during normal operation.  Use the avg_lat value as a basis for
-your real setting, setting at 10-15% higher than the value in io.stat.
+Start at higher than the expected latency for your device and, with
+blkcg_debug_stats enabled, watch the avg_lat value in io.stat for your
+workload group to get an idea of the latency you see during normal operation.
+Use the avg_lat value as a basis for your real setting, setting at 10-15%
+higher than the value in io.stat.
 
 How IO Latency Throttling Works
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
@@ -2298,7 +2299,9 @@ IO Latency Interface Files
 
   io.stat
 	If the controller is enabled you will see extra stats in io.stat in
-	addition to the normal ones.
+	addition to the normal ones.  These debug stats are only emitted when
+	the blkcg_debug_stats module parameter is enabled (it is disabled by
+	default).
 
 	  depth
 		This is the current queue depth for the group.