reproduce (this is a W=1 build):
        # https://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost.git/commit/?id=b7468115b6045e555aa8a8f2fa327c1c073fc6df
        git remote add mst-vhost https://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost.git
        git fetch --no-tags mst-vhost vhost
        git checkout b7468115b6045e555aa8a8f2fa327c1c073fc6df
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        make W=1 O=build_dir ARCH=x86_64 olddefconfig
        make W=1 O=build_dir ARCH=x86_64 SHELL=/bin/bash drivers/firmware/efi/libstub/