diff --git a/documentation/ref-manual/ref-classes.xml b/documentation/ref-manual/ref-classes.xml
index 198bfe5470..cd3924af6b 100644
--- a/documentation/ref-manual/ref-classes.xml
+++ b/documentation/ref-manual/ref-classes.xml
@@ -986,6 +986,16 @@
     </para>
 </section>
 
+<section id='ref-classes-kernel-arch'>
+    <title><filename>kernel-arch.bbclass</filename></title>
+
+    <para>
+        The kernel architecture (<filename>kernel-arch</filename>) class
+        sets the <filename>ARCH</filename> environment variable for Linux
+        kernel compilation (including modules).
+    </para>
+</section>
+
 <section id='ref-classes-mime'>
     <title><filename>mime.bbclass</filename></title>