--- a/hotspot/src/os/linux/vm/os_linux.cpp	Fri Mar 28 11:52:29 2008 -0700
+++ b/hotspot/src/os/linux/vm/os_linux.cpp	Fri Mar 28 23:35:42 2008 -0700
@@ -2480,6 +2480,10 @@
   return false;
 }
 
+bool os::can_execute_large_page_memory() {
+  return false;
+}
+
 // Reserve memory at an arbitrary address, only if that area is
 // available (and not reserved for something else).
 

--- a/hotspot/src/os/solaris/vm/os_solaris.cpp	Fri Mar 28 11:52:29 2008 -0700
+++ b/hotspot/src/os/solaris/vm/os_solaris.cpp	Fri Mar 28 23:35:42 2008 -0700
@@ -3089,6 +3089,8 @@
   if (UseISM) {
     // ISM disables MPSS to be compatible with old JDK behavior
     UseMPSS = false;
+    _page_sizes[0] = _large_page_size;
+    _page_sizes[1] = vm_page_size();
   }
 
   UseMPSS = UseMPSS &&
@@ -3178,6 +3180,10 @@
   return UseISM ? false : true;
 }
 
+bool os::can_execute_large_page_memory() {
+  return UseISM ? false : true;
+}
+
 static int os_sleep(jlong millis, bool interruptible) {
   const jlong limit = INT_MAX;
   jlong prevtime;

--- a/hotspot/src/os/windows/vm/os_windows.cpp	Fri Mar 28 11:52:29 2008 -0700
+++ b/hotspot/src/os/windows/vm/os_windows.cpp	Fri Mar 28 23:35:42 2008 -0700
@@ -2516,9 +2516,13 @@
   return false;
 }
 
+bool os::can_execute_large_page_memory() {
+  return true;
+}
+
 char* os::reserve_memory_special(size_t bytes) {
   DWORD flag = MEM_RESERVE | MEM_COMMIT | MEM_LARGE_PAGES;
-  char * res = (char *)VirtualAlloc(NULL, bytes, flag, PAGE_READWRITE);
+  char * res = (char *)VirtualAlloc(NULL, bytes, flag, PAGE_EXECUTE_READWRITE);
   return res;
 }
 

--- a/hotspot/src/share/vm/gc_implementation/parallelScavenge/parMarkBitMap.cpp	Fri Mar 28 11:52:29 2008 -0700
+++ b/hotspot/src/share/vm/gc_implementation/parallelScavenge/parMarkBitMap.cpp	Fri Mar 28 23:35:42 2008 -0700
@@ -41,7 +41,7 @@
 
   const size_t rs_align = page_sz == (size_t) os::vm_page_size() ? 0 :
     MAX2(page_sz, granularity);
-  ReservedSpace rs(bytes, rs_align, false);
+  ReservedSpace rs(bytes, rs_align, rs_align > 0);
   os::trace_page_sizes("par bitmap", raw_bytes, raw_bytes, page_sz,
                        rs.base(), rs.size());
   _virtual_space = new PSVirtualSpace(rs, page_sz);

--- a/hotspot/src/share/vm/gc_implementation/parallelScavenge/psParallelCompact.cpp	Fri Mar 28 11:52:29 2008 -0700
+++ b/hotspot/src/share/vm/gc_implementation/parallelScavenge/psParallelCompact.cpp	Fri Mar 28 23:35:42 2008 -0700
@@ -413,7 +413,7 @@
 
   const size_t rs_align = page_sz == (size_t) os::vm_page_size() ? 0 :
     MAX2(page_sz, granularity);
-  ReservedSpace rs(bytes, rs_align, false);
+  ReservedSpace rs(bytes, rs_align, rs_align > 0);
   os::trace_page_sizes("par compact", raw_bytes, raw_bytes, page_sz, rs.base(),
                        rs.size());
   PSVirtualSpace* vspace = new PSVirtualSpace(rs, page_sz);

--- a/hotspot/src/share/vm/memory/heap.cpp	Fri Mar 28 11:52:29 2008 -0700
+++ b/hotspot/src/share/vm/memory/heap.cpp	Fri Mar 28 23:35:42 2008 -0700
@@ -102,8 +102,9 @@
   _log2_segment_size = exact_log2(segment_size);
 
   // Reserve and initialize space for _memory.
-  const size_t page_size = os::page_size_for_region(committed_size,
-                                                    reserved_size, 8);
+  const size_t page_size = os::can_execute_large_page_memory() ?
+          os::page_size_for_region(committed_size, reserved_size, 8) :
+          os::vm_page_size();
   const size_t granularity = os::vm_allocation_granularity();
   const size_t r_align = MAX2(page_size, granularity);
   const size_t r_size = align_size_up(reserved_size, r_align);
@@ -111,7 +112,7 @@
 
   const size_t rs_align = page_size == (size_t) os::vm_page_size() ? 0 :
     MAX2(page_size, granularity);
-  ReservedSpace rs(r_size, rs_align, false);
+  ReservedSpace rs(r_size, rs_align, rs_align > 0);
   os::trace_page_sizes("code heap", committed_size, reserved_size, page_size,
                        rs.base(), rs.size());
   if (!_memory.initialize(rs, c_size)) {

--- a/hotspot/src/share/vm/runtime/os.hpp	Fri Mar 28 11:52:29 2008 -0700
+++ b/hotspot/src/share/vm/runtime/os.hpp	Fri Mar 28 23:35:42 2008 -0700
@@ -228,6 +228,7 @@
   static bool   large_page_init();
   static size_t large_page_size();
   static bool   can_commit_large_page_memory();
+  static bool   can_execute_large_page_memory();
 
   // OS interface to polling page
   static address get_polling_page()             { return _polling_page; }