LKML https://lkml.org/ is an unofficial Linux Kernel Mailing List archive. This mailing list is a rather high-volume list, where (technical) discussions on the design of, and bugs in the Linux kernel take place. You can read more information about it at http://vger.kernel.org/lkml/
How to join Linux kernel mailing lists ?
Linux kernel has different mailing lists as per core and linux kernel subsystem’s. To join open website http://vger.kernel.org/vger-lists.html
In the opened website, you can go to the list which you want to join and click “subscribe”, and send the mail.
For example, if you want to join, “alsa-devel” mailing list, send email to “majordomo@vger.kernel.org” with body as “subscribe alsa-devel” with empty subject line.