diff --git a/ch9/src/os/mm/memory_set.rs.html b/ch9/src/os/mm/memory_set.rs.html
index 5379216a4..1352fac7c 100644
--- a/ch9/src/os/mm/memory_set.rs.html
+++ b/ch9/src/os/mm/memory_set.rs.html
@@ -457,7 +457,7 @@
pub fn push(&mut self, mut map_area: MapArea, data: Option<&[u8]>) {
map_area.map(&mut self.page_table);
if let Some(data) = data {
- map_area.copy_data(&mut self.page_table, data);
+ map_area.copy_data(&self.page_table, data);
}
self.areas.push(map_area);
}