diff --git a/[refs] b/[refs]
index c566e98dfeeb..d59f2e8d556c 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 9786bf841da57fac3457a1dac41acb4c1f2eced6
+refs/heads/master: bd775c42ea5f7c766d03a287083837cf05e7e738
diff --git a/trunk/mm/memory.c b/trunk/mm/memory.c
index 0017111214c5..5b4ad5e4f98d 100644
--- a/trunk/mm/memory.c
+++ b/trunk/mm/memory.c
@@ -1151,6 +1151,11 @@ struct page *follow_page(struct vm_area_struct *vma, unsigned long address,
 		if ((flags & FOLL_WRITE) &&
 		    !pte_dirty(pte) && !PageDirty(page))
 			set_page_dirty(page);
+		/*
+		 * pte_mkyoung() would be more correct here, but atomic care
+		 * is needed to avoid losing the dirty bit: it is easier to use
+		 * mark_page_accessed().
+		 */
 		mark_page_accessed(page);
 	}
 unlock: