diff --git a/mm/page_isolation.c b/mm/page_isolation.c
index d200d41ad0d3..9d73dc38e3d7 100644
--- a/mm/page_isolation.c
+++ b/mm/page_isolation.c
@@ -286,6 +286,8 @@ __first_valid_page(unsigned long pfn, unsigned long nr_pages)
  * @flags:			isolation flags
  * @gfp_flags:			GFP flags used for migrating pages
  * @isolate_before:	isolate the pageblock before the boundary_pfn
+ * @skip_isolation:	the flag to skip the pageblock isolation in second
+ *			isolate_single_pageblock()
  *
  * Free and in-use pages can be as big as MAX_ORDER-1 and contain more than one
  * pageblock. When not all pageblocks within a page are isolated at the same