reproduce (this is a W=1 build):
        # https://github.com/projectacrn/acrn-kernel/commit/9ec53c7650a0ddf3081191667b88940dd415a3a3
        git remote add acrn https://github.com/projectacrn/acrn-kernel
        git fetch --no-tags acrn 6.12/linux
        git checkout 9ec53c7650a0ddf3081191667b88940dd415a3a3
        git clone https://github.com/intel/lkp-tests.git ~/lkp-tests
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.5.0 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=s390 olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.5.0 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=s390 SHELL=/bin/bash mm/