Index: /trunk/src/VBox/VMM/PGM.cpp
===================================================================
--- /trunk/src/VBox/VMM/PGM.cpp	(revision 30907)
+++ /trunk/src/VBox/VMM/PGM.cpp	(revision 30908)
@@ -2051,5 +2051,6 @@
          *        address width is relevant.  See table 5-9 in the intel
          *        manual vs the PDE4M descriptions.  Write testcase (NP). */
-        pVCpu->pgm.s.fGst32BitMbzBigPdeMask  = (uint32_t)(fMbzPageFrameMask >> (32 - 13)) | X86_PDE4M_MBZ_MASK;
+        pVCpu->pgm.s.fGst32BitMbzBigPdeMask  = ((uint32_t)(fMbzPageFrameMask >> (32 - 13)) & X86_PDE4M_PG_HIGH_MASK)
+                                             | X86_PDE4M_MBZ_MASK;
 
         pVCpu->pgm.s.fGstPaeMbzPteMask       = fMbzPageFrameMask | X86_PTE_PAE_MBZ_MASK_NO_NX;