diff --git a/include/linux/gfp.h b/include/linux/gfp.h
index 31e8041274f6ce32fec6b69cf1197f5c5f31b74b..f74856e17e488deb9698f610511fcfed44f35ba3 100644
--- a/include/linux/gfp.h
+++ b/include/linux/gfp.h
@@ -34,6 +34,7 @@ struct vm_area_struct;
 #define ___GFP_NO_KSWAPD	0x400000u
 #define ___GFP_OTHER_NODE	0x800000u
 #define ___GFP_WRITE		0x1000000u
+/* If the above are modified, __GFP_BITS_SHIFT may need updating */
 
 /*
  * GFP bitmasks..