reproduce (this is a W=1 build):
        git clone https://github.com/intel/lkp-tests.git ~/lkp-tests
        # https://github.com/awilliam/linux-vfio/commit/e93ffb9dfe21dc8f7f91afb6947bf30fff79d9a6
        git remote add awilliam-vfio https://github.com/awilliam/linux-vfio.git
        git fetch --no-tags awilliam-vfio vfio-huge-fault
        git checkout e93ffb9dfe21dc8f7f91afb6947bf30fff79d9a6
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-14.1.0 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=s390 olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-14.1.0 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=s390 SHELL=/bin/bash arch/s390/pci/