diff --git a/reactos/ntoskrnl/ke/i386/exp.c b/reactos/ntoskrnl/ke/i386/exp.c
index cc2683648a9..65a2919568a 100644
--- a/reactos/ntoskrnl/ke/i386/exp.c
+++ b/reactos/ntoskrnl/ke/i386/exp.c
@@ -469,7 +469,7 @@ KiTrapHandler(PKTRAP_FRAME Tf, ULONG ExceptionNr)
  *        Complete CPU context
  */
 {
-   unsigned int cr2;
+   ULONG_PTR cr2;
    NTSTATUS Status;
    ULONG Esp0;
 
@@ -528,7 +528,7 @@ KiTrapHandler(PKTRAP_FRAME Tf, ULONG ExceptionNr)
     */
    if (ExceptionNr == 14)
      {
-        if (Ke386NoExecute && Tf->ErrorCode & 0x10 && cr2 >= KERNEL_BASE)
+        if (Ke386NoExecute && Tf->ErrorCode & 0x10 && cr2 >= (ULONG_PTR)MmSystemRangeStart)
 	{
            KEBUGCHECKWITHTF(ATTEMPTED_EXECUTE_OF_NOEXECUTE_MEMORY, 0, 0, 0, 0, Tf);
 	}
diff --git a/reactos/ntoskrnl/mm/marea.c b/reactos/ntoskrnl/mm/marea.c
index 10c8283ce42..87fabbd9fc8 100644
--- a/reactos/ntoskrnl/mm/marea.c
+++ b/reactos/ntoskrnl/mm/marea.c
@@ -971,7 +971,7 @@ MmCreateMemoryArea(PEPROCESS Process,
       *BaseAddress = MM_ROUND_DOWN(*BaseAddress, Granularity);
 
       if (AddressSpace->LowestAddress == MmSystemRangeStart &&
-          *BaseAddress < (PVOID)KERNEL_BASE)
+          *BaseAddress < MmSystemRangeStart)
       {
          CHECKPOINT;
          return STATUS_ACCESS_VIOLATION;