reproduce (this is a W=1 build):
        git clone https://github.com/intel/lkp-tests.git ~/lkp-tests
        # https://github.com/intel/tdx/commit/cd0e3e3e24066f4045d103aa466affe1af30c385
        git remote add intel-tdx https://github.com/intel/tdx.git
        git fetch --no-tags intel-tdx huge_page_v2
        git checkout cd0e3e3e24066f4045d103aa466affe1af30c385
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-15.1.0 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=s390 olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-15.1.0 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=s390 SHELL=/bin/bash