reproduce (this is a W=1 build):
        git remote add mst-vhost https://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost.git
        git fetch mst-vhost linux-next
        git checkout mst-vhost/linux-next
        b4 shazam https://lore.kernel.org/r/20251027102644.622305-1-nhudson@akamai.com

        git clone https://github.com/intel/lkp-tests.git ~/lkp-tests

        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-15.1.0 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=csky olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-15.1.0 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=csky SHELL=/bin/bash drivers/vhost/