reproduce (this is a W=1 build):
        git clone https://github.com/intel/lkp-tests.git ~/lkp-tests
        # https://github.com/avpatel/linux/commit/27efa9d6d5ee0de25edcc278388909f36832e5bc
        git remote add avpatel https://github.com/avpatel/linux.git
        git fetch --no-tags avpatel riscv_raid6_rvv_v3
        git checkout 27efa9d6d5ee0de25edcc278388909f36832e5bc
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-14.2.0 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=riscv olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-14.2.0 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=riscv SHELL=/bin/bash arch/riscv/kernel/ kernel/