reproduce (this is a W=1 build):
        git clone https://github.com/intel/lkp-tests.git ~/lkp-tests
        # https://github.com/rgushchin/linux/commit/6de83397e2150cad0ca5ee7ce49a1fd8cf05f4f1
        git remote add rgushchin https://github.com/rgushchin/linux.git
        git fetch --no-tags rgushchin bpfoom.1.5
        git checkout 6de83397e2150cad0ca5ee7ce49a1fd8cf05f4f1
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.5.0 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=csky olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.5.0 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=csky SHELL=/bin/bash kernel/