--- a/hotspot/src/os/linux/vm/os_linux.cpp	Mon Mar 23 10:42:20 2009 -0400
+++ b/hotspot/src/os/linux/vm/os_linux.cpp	Wed Mar 25 14:19:20 2009 -0400
@@ -2269,15 +2269,16 @@
 //       All it does is to check if there are enough free pages
 //       left at the time of mmap(). This could be a potential
 //       problem.
-bool os::commit_memory(char* addr, size_t size) {
-  uintptr_t res = (uintptr_t) ::mmap(addr, size,
-                                   PROT_READ|PROT_WRITE|PROT_EXEC,
+bool os::commit_memory(char* addr, size_t size, bool exec) {
+  int prot = exec ? PROT_READ|PROT_WRITE|PROT_EXEC : PROT_READ|PROT_WRITE;
+  uintptr_t res = (uintptr_t) ::mmap(addr, size, prot,
                                    MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0);
   return res != (uintptr_t) MAP_FAILED;
 }
 
-bool os::commit_memory(char* addr, size_t size, size_t alignment_hint) {
-  return commit_memory(addr, size);
+bool os::commit_memory(char* addr, size_t size, size_t alignment_hint,
+                       bool exec) {
+  return commit_memory(addr, size, exec);
 }
 
 void os::realign_memory(char *addr, size_t bytes, size_t alignment_hint) { }
@@ -2417,8 +2418,7 @@
 unsigned long* os::Linux::_numa_all_nodes;
 
 bool os::uncommit_memory(char* addr, size_t size) {
-  return ::mmap(addr, size,
-                PROT_READ|PROT_WRITE|PROT_EXEC,
+  return ::mmap(addr, size, PROT_NONE,
                 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE|MAP_ANONYMOUS, -1, 0)
     != MAP_FAILED;
 }
@@ -2441,7 +2441,9 @@
     flags |= MAP_FIXED;
   }
 
-  addr = (char*)::mmap(requested_addr, bytes, PROT_READ|PROT_WRITE|PROT_EXEC,
+  // Map uncommitted pages PROT_READ and PROT_WRITE, change access
+  // to PROT_EXEC if executable when we commit the page.
+  addr = (char*)::mmap(requested_addr, bytes, PROT_READ|PROT_WRITE,
                        flags, -1, 0);
 
   if (addr != MAP_FAILED) {
@@ -2582,7 +2584,9 @@
 #define SHM_HUGETLB 04000
 #endif
 
-char* os::reserve_memory_special(size_t bytes, char* req_addr) {
+char* os::reserve_memory_special(size_t bytes, char* req_addr, bool exec) {
+  // "exec" is passed in but not used.  Creating the shared image for
+  // the code cache doesn't have an SHM_X executable permission to check.
   assert(UseLargePages, "only for large pages");
 
   key_t key = IPC_PRIVATE;