reproduce (this is a W=1 build):
        git clone https://github.com/intel/lkp-tests.git ~/lkp-tests
        # https://github.com/oracle/dtrace-linux-kernel/commit/31f9ac854b10569bf09153d7757efb17468df8bb
        git remote add oracle-dtrace https://github.com/oracle/dtrace-linux-kernel
        git fetch --no-tags oracle-dtrace v2/6.6
        git checkout 31f9ac854b10569bf09153d7757efb17468df8bb
        # 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