diff --git a/bsp/qemu-vexpress-a9/.config b/bsp/qemu-vexpress-a9/.config
index 82f7bf0f4a5fc4872857a8dc7a64192bfdadf17d..1734cf89ac1e6c5f826af35a7031b4df3aef0904 100644
--- a/bsp/qemu-vexpress-a9/.config
+++ b/bsp/qemu-vexpress-a9/.config
@@ -151,7 +151,7 @@ CONFIG_RT_USING_WDT=y
 CONFIG_RT_USING_LIBC=y
 CONFIG_RT_USING_PTHREADS=y
 CONFIG_RT_USING_POSIX=y
-# CONFIG_RT_USING_POSIX_MMAP is not set
+CONFIG_RT_USING_POSIX_MMAP=y
 CONFIG_RT_USING_POSIX_TERMIOS=y
 
 #
diff --git a/bsp/qemu-vexpress-a9/rtconfig.h b/bsp/qemu-vexpress-a9/rtconfig.h
index 5e8213cf700600b6d8d69edd8da2f5834f9d76a7..c6cd1939bee481b7d7bf9f27ca0da5a894419a02 100644
--- a/bsp/qemu-vexpress-a9/rtconfig.h
+++ b/bsp/qemu-vexpress-a9/rtconfig.h
@@ -140,7 +140,7 @@
 #define RT_USING_LIBC
 #define RT_USING_PTHREADS
 #define RT_USING_POSIX
-/* RT_USING_POSIX_MMAP is not set */
+#define RT_USING_POSIX_MMAP
 #define RT_USING_POSIX_TERMIOS
 
 /* Network stack */