From: Ben Pfaff <blp@cs.stanford.edu>
Date: Mon, 20 Sep 2004 22:25:28 +0000 (+0000)
Subject: Make pagedir_destroy(NULL) a no-op.
X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?p=pintos-anon;a=commitdiff_plain;h=c9d2f441f65d0c3a92938df02a752e6c78de487d

Make pagedir_destroy(NULL) a no-op.
---

diff --git a/src/userprog/pagedir.c b/src/userprog/pagedir.c
index bfcda45..1edd0ff 100644
--- a/src/userprog/pagedir.c
+++ b/src/userprog/pagedir.c
@@ -19,6 +19,9 @@ pagedir_destroy (uint32_t *pd)
 {
   uint32_t *pde;
 
+  if (pd == NULL)
+    return;
+
   for (pde = pd; pde < pd + pd_no (PHYS_BASE); pde++)
     if (*pde & PG_P) 
       {