http://www.gentoo.org/doc/en/udev-guide.xml In past, it used to describe how to blacklist kernel modules. Nowadays it doesn't. I believe the guide should be expanded, adding back that information. http://web.archive.org/web/20130128044912/http://www.gentoo.org/doc/en/udev-guide.xml
This document has been marked as obsolete. However, a more active document can be found on the Gentoo Wiki at https://wiki.gentoo.org/wiki/Udev. We welcome any contributions on this guide and recommend you create an account (if you do not have one already) and make the adjustments to the article as needed. In case of doubt, use the Talk page to discuss potential changes before applying them. If needed, the wiki-style version of the old document is available at https://wiki.gentoo.org/wiki/User:SwifT/Wikified_but_not_merged_documents/Udev_guide so any previously existing content can, if needed, be reused on the wiki.