reproduce (this is a W=1 build):
        git clone https://github.com/intel/lkp-tests.git ~/lkp-tests
        # https://github.com/xinli-intel/linux-fred-public/commit/358a2ad2be426f7146d59083b1398d9cb1c2ebe7
        git remote add xinli-intel-fred-public https://github.com/xinli-intel/linux-fred-public.git
        git fetch --no-tags xinli-intel-fred-public intel-lkp
        git checkout 358a2ad2be426f7146d59083b1398d9cb1c2ebe7
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang-20 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=i386 olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang-20 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=i386 SHELL=/bin/bash arch/x86/kernel/cpu/resctrl/