diff --git a/board/impa7/flash.c b/board/impa7/flash.c
index c59ffb8..7db0b32 100644
--- a/board/impa7/flash.c
+++ b/board/impa7/flash.c
@@ -72,7 +72,7 @@
      */
     flash_protect(FLAG_PROTECT_SET,
 		  CFG_FLASH_BASE,
-		  CFG_FLASH_BASE + _armboot_end_data - _armboot_start,
+		  CFG_FLASH_BASE + monitor_flash_len - 1,
 		  &flash_info[0]);
 
     flash_protect(FLAG_PROTECT_SET,