reproduce:
        git clone https://github.com/intel/lkp-tests.git ~/lkp-tests
        # apt-get install sparse
        # sparse version: v0.6.4-66-g0196afe1
        # https://github.com/intel-lab-lkp/linux/commit/2c1d93ee4c4e54d59adc7b6e8ddd28c33e4819ff
        git remote add linux-review https://github.com/intel-lab-lkp/linux
        git fetch --no-tags linux-review Roman-Kisel/arm64-kvm-smccc-Introduce-and-use-API-for-detecting-hypervisor-presence/20250315-082319
        git checkout 2c1d93ee4c4e54d59adc7b6e8ddd28c33e4819ff
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-14.2.0 ~/lkp-tests/kbuild/make.cross C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__ -fmax-errors=unlimited -fmax-warnings=unlimited' O=build_dir ARCH=arm64 olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-14.2.0 ~/lkp-tests/kbuild/make.cross C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__ -fmax-errors=unlimited -fmax-warnings=unlimited' O=build_dir ARCH=arm64 SHELL=/bin/bash arch/arm64/kvm/