reproduce (this is a W=1 build):
        git remote add kvm https://git.kernel.org/pub/scm/virt/kvm/kvm.git
        git fetch kvm queue
        git checkout kvm/queue
        b4 shazam https://lore.kernel.org/r/20251021083105.4029305-1-minachou@andestech.com

        # install riscv cross compiling tool for clang build
        # apt-get install binutils-riscv64-linux-gnu
        # clang-22 might not be officially released. Try a lower version if installation fails.
        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=$HOME/0day COMPILER=clang-22 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=riscv olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang-22 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=riscv SHELL=/bin/bash arch/riscv/kvm/