reproduce (this is a W=1 build):
        git remote add ti git://git.ti.com/ti-linux-kernel/ti-linux-kernel.git
        git fetch --no-tags ti ti-rt-linux-6.1.y-cicd
        git checkout d4da27218fd9cf1f7f606ff65c7a63e87f9139cc
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        make W=1 O=build_dir ARCH=um olddefconfig
        make W=1 O=build_dir ARCH=um SHELL=/bin/bash