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/vfs/vfs.git/commit/?id=9ce83f52a131f8806989e05df19215c433c8e7c8
        git remote add brauner-vfs https://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs.git
        git fetch --no-tags brauner-vfs work.coredump.socket.protocol
        git checkout 9ce83f52a131f8806989e05df19215c433c8e7c8
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.4.0 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=csky olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.4.0 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=csky SHELL=/bin/bash