diff -r 0a1955ae9f9b xen/arch/x86/hvm/hvm.c
--- a/xen/arch/x86/hvm/hvm.c    Tue Oct 30 10:25:17 2007 -0600
+++ b/xen/arch/x86/hvm/hvm.c    Tue Oct 30 11:04:59 2007 -0600
@@ -49,8 +49,17 @@
 #include <public/version.h>
 #include <public/memory.h>
 
-/* Xen command-line option to disable hardware-assisted paging */
-static int opt_hap_disabled;
+/* Xen command-line option to disable hardware-assisted paging 
+ * 
+ * Since phys-to-machine table of NPT is in host format, 32-bit Xen could only
+ * support guests using NPT with up to a 4GB memory map. Therefore we only
+ * enable HAP as default for 64bit.
+ */
+#ifdef __x86_64__
+static int opt_hap_disabled = 0;
+#else
+static int opt_hap_disabled = 1;
+#endif
 invbool_param("hap", opt_hap_disabled);
 
 int hvm_enabled __read_mostly;
@@ -83,9 +92,10 @@ void hvm_enable(struct hvm_function_tabl
     {
         if ( opt_hap_disabled )
             hvm_funcs.hap_supported = 0;
-        printk("HVM: Hardware Assisted Paging %sabled\n",
-               hvm_funcs.hap_supported ? "en" : "dis");
-    }
+    }
+
+    printk("HVM: Hardware Assisted Paging %sabled\n",
+           hvm_funcs.hap_supported ? "en" : "dis");
 }
 
 void hvm_set_guest_time(struct vcpu *v, u64 gtime)
diff -r 0a1955ae9f9b xen/arch/x86/hvm/svm/svm.c
--- a/xen/arch/x86/hvm/svm/svm.c        Tue Oct 30 10:25:17 2007 -0600
+++ b/xen/arch/x86/hvm/svm/svm.c        Tue Oct 30 10:49:33 2007 -0600
@@ -940,14 +940,7 @@ int start_svm(struct cpuinfo_x86 *c)
     svm_feature_flags = ((cpuid_eax(0x80000000) >= 0x8000000A) ?
                          cpuid_edx(0x8000000A) : 0);
 
-#ifdef __x86_64__
-    /*
-     * Check CPUID for nested paging support. We support NPT only on 64-bit
-     * hosts since the phys-to-machine table is in host format. Hence 32-bit
-     * Xen could only support guests using NPT with up to a 4GB memory map.
-     */
     svm_function_table.hap_supported = cpu_has_svm_npt;
-#endif
 
     hvm_enable(&svm_function_table);