diff --git a/benchmark/space/__init__.py b/benchmark/space/__init__.py
index fc193ff..849c02e 100644
--- a/benchmark/space/__init__.py
+++ b/benchmark/space/__init__.py
@@ -489,9 +489,9 @@ class BENCHMARK_OT_run_base(bpy.types.Operator):
         # TOGO(sergey): Use some more nice picture for the final slide.
         G.background_image_path = ""
         # Tag for nice redraw
-        # TODO(Sybren): lock G.progress_lock
-        G.progress_status = None
-        G.current_progress = 0.0
+        with G.progress_lock:
+            G.progress_status = ''
+            G.current_progress = 0.0
         context.area.tag_redraw()
         self.tmpdir = None