diff --git a/clutter/cogl/cogl/cogl-buffer.c b/clutter/cogl/cogl/cogl-buffer.c
index 1000d74dc..a4e9e66c5 100644
--- a/clutter/cogl/cogl/cogl-buffer.c
+++ b/clutter/cogl/cogl/cogl-buffer.c
@@ -132,8 +132,7 @@ _cogl_buffer_initialize (CoglBuffer           *buffer,
 void
 _cogl_buffer_fini (CoglBuffer *buffer)
 {
-  if (COGL_BUFFER_FLAG_IS_SET (buffer, MAPPED))
-    cogl_buffer_unmap (buffer);
+  g_return_if_fail (!COGL_BUFFER_FLAG_IS_SET (buffer, MAPPED));
 }
 
 GLenum
diff --git a/clutter/cogl/cogl/cogl-buffer.h b/clutter/cogl/cogl/cogl-buffer.h
index 7c61b51dc..8ad45a233 100644
--- a/clutter/cogl/cogl/cogl-buffer.h
+++ b/clutter/cogl/cogl/cogl-buffer.h
@@ -191,7 +191,8 @@ typedef enum { /*< prefix=COGL_BUFFER_MAP_HINT >*/
  * new buffer to map.
  *
  * The behaviour is undefined if you access the buffer in a way
- * conflicting with the @access mask you pass.
+ * conflicting with the @access mask you pass. It is also an error to
+ * release your last reference while the buffer is mapped.
  *
  * Return value: A pointer to the mapped memory or %NULL is the call fails
  *