@bob Yes, that's a later issue, when my distro's actually upgrade to 4.17 (Ubuntu is doing it during 18.10). But according that Itsfoss article I can:
"If it doesn’t exist already, create /etc/modprobe.d/blacklist.conf file and add the following lines to it:
blacklist CONFIG_CRYPTO_SPECK
"
So my question is more; can I blacklist not yet existing modules?