diff --git a/configs/stm32f429-discovery_defconfig b/configs/stm32f429-discovery_defconfig
index f7d3fc2..c554d2d 100644
--- a/configs/stm32f429-discovery_defconfig
+++ b/configs/stm32f429-discovery_defconfig
@@ -2,6 +2,7 @@
 CONFIG_STM32=y
 CONFIG_STM32F4=y
 CONFIG_TARGET_STM32F429_DISCOVERY=y
+# CONFIG_MMC is not set
 CONFIG_BOOTDELAY=3
 # CONFIG_DISPLAY_CPUINFO is not set
 # CONFIG_DISPLAY_BOARDINFO is not set