diff --git a/src/hb-kern.hh b/src/hb-kern.hh
index debfbb1ce..943631932 100644
--- a/src/hb-kern.hh
+++ b/src/hb-kern.hh
@@ -49,6 +49,9 @@ struct hb_kern_machine_t
 	     hb_mask_t    kern_mask,
 	     bool         scale = true) const
   {
+    if (!buffer->message (font, "start kern"))
+      return;
+
     buffer->set_glyph_flags (HB_GLYPH_FLAG_UNSAFE_TO_CONCAT);
     OT::hb_ot_apply_context_t c (1, font, buffer);
     c.set_lookup_mask (kern_mask);
@@ -127,6 +130,8 @@ struct hb_kern_machine_t
     skip:
       idx = skippy_iter.idx;
     }
+
+    (void) buffer->message (font, "end kern");
   }
 
   const Driver &driver;
diff --git a/src/hb-ot-shape-fallback.cc b/src/hb-ot-shape-fallback.cc
index 0fae26389..671f30327 100644
--- a/src/hb-ot-shape-fallback.cc
+++ b/src/hb-ot-shape-fallback.cc
@@ -446,6 +446,9 @@ _hb_ot_shape_fallback_mark_position (const hb_ot_shape_plan_t *plan,
   return;
 #endif
 
+  if (!buffer->message (font, "start fallback mark"))
+    return;
+
   _hb_buffer_assert_gsubgpos_vars (buffer);
 
   unsigned int start = 0;
@@ -457,6 +460,8 @@ _hb_ot_shape_fallback_mark_position (const hb_ot_shape_plan_t *plan,
       start = i;
     }
   position_cluster (plan, font, buffer, start, count, adjust_offsets_when_zeroing);
+
+  (void) buffer->message (font, "end fallback mark");
 }
 
 
@@ -492,6 +497,9 @@ _hb_ot_shape_fallback_kern (const hb_ot_shape_plan_t *plan,
 #endif
 
 #ifndef HB_DISABLE_DEPRECATED
+  if (!buffer->message (font, "start fallback kern"))
+    return;
+
   if (HB_DIRECTION_IS_HORIZONTAL (buffer->props.direction) ?
       !font->has_glyph_h_kerning_func () :
       !font->has_glyph_v_kerning_func ())
@@ -508,6 +516,8 @@ _hb_ot_shape_fallback_kern (const hb_ot_shape_plan_t *plan,
 
   if (reverse)
     buffer->reverse ();
+
+  (void) buffer->message (font, "end fallback kern");
 #endif
 }