diff --git a/diff-hl.el b/diff-hl.el
index e61c40f4..70e3f7ba 100644
--- a/diff-hl.el
+++ b/diff-hl.el
@@ -645,9 +645,8 @@ contents as they are (or would be) after applying the changes in NEW."
     (diff-hl--update)))
 
 (defun diff-hl--update-buffer (buf)
-  (when (buffer-live-p buf)
-    (with-current-buffer buf
-      (diff-hl-update))))
+  (with-current-buffer buf
+    (diff-hl-update)))
 
 (defun diff-hl-with-editor-p (_dir)
   (bound-and-true-p with-editor-mode))