Here is a patch, which adds support for CAN_RAW_JOIN_FILTERS which is available since linux 4.1 [1]. My patch fixes trailing whitespace issues as well. Since I have a newer version of autotools, running "autoreconf" generates a lot of changes, so I left that out for the time being.

[1]: https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=a5581ef4c2eac6449188862e903eb46c7233582a

in case you don't like whitespace cleanups, here is the patch with "git diff --ignore-space-changes".

Not sure what the general policy is, but IMO it is better to leave offensive white space as it is to avoid flooding the file history and diffs, unless you are editing nearby lines.

I will leave some review comments for the documentation.

In this particular case, whether we want to do that to config.ac is a separate question and should be addressed in a separate issue.

Because is the first time I work with this bugtracking system on python.org, how can I update my patch? :) Just upload a new one?

Yes.  The review system will automatically include the new patch, regardless of its name (it looks at the content).

Thanks! Here is an update.

The other thing for new features is test cases. I don’t know if there are any existing CAN socket tests (in fact I don’t know anything about CAN sockets). Is it possible to make a test for this? Even if it just ensures that the setting can be applied when supported. Though I guess if this is too hard it may not be worth it.

Hmm. I just adapted this feature request from issue22631 for the new constant and I verified that my patch actually works. I could try to provide a test, but then I would have to open Pandora's box as I am not a CPython developer at all. :/

New changeset 97e0de04b8cd44474e452a028761e34407192041 by Zackery Spytz in branch 'master':
bpo-25780: Expose CAN_RAW_JOIN_FILTERS in the socket module (GH-19190)
https://github.com/python/cpython/commit/97e0de04b8cd44474e452a028761e34407192041