reproduce (this is a W=1 build):
        # https://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux.git/commit/?id=60116744be534090c62686f441dc16f36dd7e42e
        git remote add hyperv https://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux.git
        git fetch --no-tags hyperv hyperv-next
        git checkout 60116744be534090c62686f441dc16f36dd7e42e

        # save the config file
        mkdir build_dir && cp config build_dir/.config
        make W=1 O=build_dir ARCH=x86_64 olddefconfig
        make W=1 O=build_dir ARCH=x86_64 SHELL=/bin/bash