diff --git a/.dir-locals.el b/.dir-locals.el
index 4b5393198de12..5340c3ae23fd8 100644
--- a/.dir-locals.el
+++ b/.dir-locals.el
@@ -1,4 +1,5 @@
-((prog-mode
+((nil . ((show-trailing-whitespace . t)))
+ (prog-mode
   (indent-tabs-mode . nil)
   (tab-width . 8)
   (c-basic-offset . 3)
@@ -8,6 +9,10 @@
 	    (c-set-offset 'case-label '0)
 	    (c-set-offset 'innamespace '0)
 	    (c-set-offset 'inline-open '0)))
-  )
+  (whitespace-style face indentation)
+  (whitespace-line-column . 79)
+  (eval ignore-errors
+        (require 'whitespace)
+        (whitespace-mode 1)))
  (makefile-mode (indent-tabs-mode . t))
  )