These are the primary Mesa 3D / DRI mailing lists:
mesa-users - intended for end-users of Mesa and DRI drivers. Newbie questions are OK, but please try the general OpenGL resources and Mesa/DRI documentation first.
mesa-dev - for Mesa, Gallium and DRI development discussion. Not for beginners.
mesa-commit - relays Git check-in messages (for developers). In general, people should not post to this list.
mesa-announce - announcements of new Mesa versions are sent to this list. Very low traffic.
dri-devel - for the Linux/BSD Direct Rendering Module (DRM) kernel modules supporting Mesa’s userspace drivers
piglit - for Piglit (OpenGL driver testing framework) discussion.
You must subscribe to these lists in order to post to them. If you try to post to a list and you’re not a subscriber (or if you try to post from a different email address than you subscribed with) your posting will be held for an indefinite period or may be discarded entirely.
Follow the links above for list archives.