reproduce (this is a W=1 build):
        git remote add jonmason-ntb https://github.com/jonmason/ntb
        git fetch jonmason-ntb ntb-next
        git checkout jonmason-ntb/ntb-next
        b4 shazam https://lore.kernel.org/r/20251023071916.901355-18-den@valinux.co.jp

        # 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