reproduce (this is a W=1 build):
        git clone https://github.com/intel/lkp-tests.git ~/lkp-tests
        # https://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson.git/commit/?id=6727d355ff23b5d9752393d403a41c7d85c7f4ee
        git remote add chenhuacai-loongson https://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson.git
        git fetch --no-tags chenhuacai-loongson loongarch-next
        git checkout 6727d355ff23b5d9752393d403a41c7d85c7f4ee
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-15.1.0 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=loongarch olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-15.1.0 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=loongarch SHELL=/bin/bash arch/loongarch/kvm/