reproduce (this is a W=1 build):
        git clone https://github.com/intel/lkp-tests.git ~/lkp-tests
        # https://github.com/davidhildenbrand/linux/commit/ba0cdf5bbe4b3e02d7732910f4f1323aef57de10
        git remote add davidhildenbrand https://github.com/davidhildenbrand/linux
        git fetch --no-tags davidhildenbrand virtio-mem-pg-offline
        git checkout ba0cdf5bbe4b3e02d7732910f4f1323aef57de10
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-13.2.0 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=powerpc olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-13.2.0 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=powerpc SHELL=/bin/bash