Only destroy pages up to PHYS_BASE.

diff --git a/src/userprog/pagedir.c b/src/userprog/pagedir.c
index 1bad9b2cc8c7fde6baa6124ed06c9f6945e7cb60..39a8f0a3af286f9227cf7d7226f19b7cd18e50e4 100644 (file)
--- a/src/userprog/pagedir.c
+++ b/src/userprog/pagedir.c
@@ -19,7 +19,7 @@ pagedir_destroy (uint32_t *pd)
 {
   uint32_t *pde;
 
-  for (pde = pd; pde < pd + PGSIZE / sizeof *pde; pde++)
+  for (pde = pd; pde < pd + pd_no (PHYS_BASE); pde++)
     if (*pde & PG_P) 
       {
         uint32_t *pt = pde_get_pt (*pde);