diff --git a/driver/common/vx_utils.h b/driver/common/vx_utils.h
index 0bac7394..e9d6cc1f 100644
--- a/driver/common/vx_utils.h
+++ b/driver/common/vx_utils.h
@@ -7,6 +7,12 @@ uint64_t aligned_size(uint64_t size, uint64_t alignment);
 bool is_aligned(uint64_t addr, uint64_t alignment);
 
 #define CACHE_BLOCK_SIZE    64
-#define ALLOC_BASE_ADDR     0x00000000
-#define LOCAL_MEM_SIZE      4294967296     // 4 GB 
+// NOTE(hansung): This is changed to something more akin to be in a heap area
+// for a CPU userspace program, since that works better with Chipyard's default
+// memory mapping scheme (0x80000000 and above).  This gives us a pretty small
+// space though.
+#define ALLOC_BASE_ADDR     0xc0000000ul
+#define LOCAL_MEM_SIZE      0x40000000ul     // 1 GB 
+// #define ALLOC_BASE_ADDR     0x00000000
+// #define LOCAL_MEM_SIZE      4294967296     // 4 GB 
 #define DEVICE_MAX_ADDR     0xfffffffful