reproduce (this is a W=1 build):
        git clone https://github.com/intel/lkp-tests.git ~/lkp-tests
        git checkout e492fac3657b60b8dd78a6e8ca26d1d14706c7b3
        b4 shazam https://lore.kernel.org/r/20250123-slub-tiny-kfree_rcu-v1-4-0e386ef1541a@suse.cz
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-13.2.0 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=arc olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-13.2.0 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=arc SHELL=/bin/bash