diff --git a/mm/nommu.c b/mm/nommu.c
index 605ace8982a8dcbc14ac061ab824166a16220180..e4b8f4d28a3f5e9bae983315f77630c21af60a3f 100644
--- a/mm/nommu.c
+++ b/mm/nommu.c
@@ -1040,10 +1040,9 @@ static int do_mmap_shared_file(struct vm_area_struct *vma)
 	if (ret != -ENOSYS)
 		return ret;
 
-	/* getting an ENOSYS error indicates that direct mmap isn't
-	 * possible (as opposed to tried but failed) so we'll fall
-	 * through to making a private copy of the data and mapping
-	 * that if we can */
+	/* getting -ENOSYS indicates that direct mmap isn't possible (as
+	 * opposed to tried but failed) so we can only give a suitable error as
+	 * it's not possible to make a private copy if MAP_SHARED was given */
 	return -ENODEV;
 }