diff --git a/src/terminal.c b/src/terminal.c
index f0ae5ed..2ad98ba 100644
--- a/src/terminal.c
+++ b/src/terminal.c
@@ -56,6 +56,7 @@
  * - GUI: when 'confirm' is set and trying to exit Vim, dialog offers to save
  *   changes to "!shell".
  *   (justrajdeep, 2017 Aug 22)
+ * - Redrawing is slow with Athena and Motif.
  * - For the GUI fill termios with default values, perhaps like pangoterm:
  *   http://bazaar.launchpad.net/~leonerd/pangoterm/trunk/view/head:/main.c#L134
  * - if the job in the terminal does not support the mouse, we can use the
@@ -2238,6 +2239,12 @@
     screen = vterm_obtain_screen(vterm);
     state = vterm_obtain_state(vterm);
 
+    if (wp->w_redr_type >= NOT_VALID)
+    {
+	term->tl_dirty_row_start = 0;
+	term->tl_dirty_row_end = MAX_ROW;
+    }
+
     /*
      * If the window was resized a redraw will be triggered and we get here.
      * Adjust the size of the vterm unless 'termsize' specifies a fixed size.