reproduce (this is a W=1 build):
        # https://github.com/cornelisnetworks/linux/commit/6f9ce1f156a4d597e2e447443a2655fb0b288337
        git remote add cornelisnetworks https://github.com/cornelisnetworks/linux.git
        git fetch --no-tags cornelisnetworks pr/1
        git checkout 6f9ce1f156a4d597e2e447443a2655fb0b288337
        # 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 drivers/infiniband/