diff --git a/Xi/extinit.c b/Xi/extinit.c
index 07ef2666d..2d077b2aa 100644
--- a/Xi/extinit.c
+++ b/Xi/extinit.c
@@ -135,8 +135,9 @@ Mask ExtExclusiveMasks[EMASKSIZE];
  * Filters for various generic events.
  * Evtype is index, mask is value at index.
  */
-static Mask xi_filters[3] = {
+static Mask xi_filters[4] = {
     XI_DeviceHierarchyChangedMask,
+    XI_DeviceClassesChangedMask,
     XI_RawDeviceEventMask,
 };