config BR2_TARGET_ROOTFS_INITRAMFS bool "initramfs for initial ramdisk of linux kernel" help Build a file which is usable for the gen_init_cpio tool at linux kernel build. This file is normally called initramfs_list and can be generated with gen_initramfs_list.sh script from the root directory structure. The file is then used in the kernel build process to generate the cpio filesystem for the initial ramdisk. Make sure that you configure this file in kernel build configuration. The location in the kernel build configuration menu is Device Drivers -> Block devices -> Initramfs source file(s). The configuration variable is CONFIG_INITRAMFS_SOURCE