1 files changed, 5 insertions, 0 deletions

diff --git a/mm/memory.c b/mm/memory.c
index 0017111214c5..5b4ad5e4f98d 100644
--- a/mm/memory.c
+++ b/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: