reproduce (this is a W=1 build):
        git clone https://github.com/intel/lkp-tests.git ~/lkp-tests
        git checkout 5723cc3450bccf7f98f227b9723b5c9f6b3af1c5
        b4 shazam https://lore.kernel.org/r/20250518-ext4-strcpy-v2-1-80d316325046@ethancedwards.com
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-10.5.0 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=csky olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-10.5.0 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=csky SHELL=/bin/bash fs/ext4/