diff --git a/configs/xenguest_arm64_defconfig b/configs/xenguest_arm64_defconfig
index fec1242..31fb4fd 100644
--- a/configs/xenguest_arm64_defconfig
+++ b/configs/xenguest_arm64_defconfig
@@ -15,6 +15,7 @@
 CONFIG_SYS_PBSIZE=1051
 # CONFIG_CMD_BDI is not set
 # CONFIG_CMD_BOOTD is not set
+CONFIG_SYS_BOOTM_LEN=0x800000
 # CONFIG_CMD_ELF is not set
 # CONFIG_CMD_GO is not set
 # CONFIG_CMD_IMI is not set