diff --git a/sys/x86/xen/xenpv.c b/sys/x86/xen/xenpv.c
index 587ced913e0a..d9db10b7005d 100644
--- a/sys/x86/xen/xenpv.c
+++ b/sys/x86/xen/xenpv.c
@@ -54,12 +54,14 @@ __FBSDID("$FreeBSD$");
  * prevent clashes with MMIO/ACPI regions.
  *
  * Since this is not possible on i386 just use any available memory
- * chunk and hope we don't clash with anything else.
+ * chunk above 1MB and hope we don't clash with anything else.
  */
 #ifdef __amd64__
 #define LOW_MEM_LIMIT	0x100000000ul
+#elif defined(__i386__)
+#define LOW_MEM_LIMIT	0x100000ul
 #else
-#define LOW_MEM_LIMIT	0
+#error "Unsupported architecture"
 #endif
 
 static devclass_t xenpv_devclass;