[gentoo-user] How recent is this Gentoo documentation?

[Meino . Cramer]

Hi,

I am on the way to configure linux-3.19.3. (vanilla) and want to start
with kexec.
On the internet via google I found this (first hit):
https://forums.gentoo.org/viewtopic-t-294644-start-0.html

I read a few lines and have a question:
Is this still up to date and useable?

Best regards,
Meino