diff --git a/mm/truncate.c b/mm/truncate.c
index 11ca480..e07b1e6 100644
--- a/mm/truncate.c
+++ b/mm/truncate.c
@@ -96,7 +96,6 @@
 		return 0;
 
 	ret = remove_mapping(mapping, page);
-	ClearPageUptodate(page);
 
 	return ret;
 }
diff --git a/mm/vmscan.c b/mm/vmscan.c
index eca7031..af73c14 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -378,6 +378,12 @@
 	return PAGE_CLEAN;
 }
 
+/*
+ * Attempt to detach a locked page from its ->mapping.  If it is dirty or if
+ * someone else has a ref on the page, abort and return 0.  If it was
+ * successfully detached, return 1.  Assumes the caller has a single ref on
+ * this page.
+ */
 int remove_mapping(struct address_space *mapping, struct page *page)
 {
 	BUG_ON(!PageLocked(page));