I have been trying to pass an option to a module, and blacklist another. I finally settled on making a modprobe.d directory to put my options into, deleting modprobe.conf and modules.conf, and leaving modules.d as is. Running modules-update regenerates modprobe.conf, but without my options in there, which is actually worse, because then modprobe doesn't look in modprobe.d. I'm frustrated by this, and the lack of documentation on how one is supposed to properly set this stuff in Gentoo, other than generic manpages.
*** This bug has been marked as a duplicate of 145962 ***