Re: Advancing the testing for the CAN subsystem

[Oliver Hartkopp <socketcan@hartkopp.net>]

Hi Felix, all,

by now I was only aware of syzbot who is sometimes showing up with some 
splats

and the Linux Test Project (LTP)

https://github.com/linux-test-project/ltp/tree/master/testcases/network/can

which e.g. provides CAN filter tests which you can also find in the 
can-tests repo.

On 20.02.25 14:03, Felix Maurer wrote:
> Hi Marc, Oliver, and linux-can community,
> 
> we are reaching out to you because we would like to advance the testing
> of the kernel CAN subsystem. We, that's Davide, Filippo and I, are
> volunteering to provide the patches for this, but would like to get your
> feedback and opinions first.

I would definitely like it and support it :-)

> We know about the can-tests repository[1] and think this is a good
> starting point for our efforts. Currently, there are two main activities
> we'd like to do:
> 
> - Promote the test cases in can-tests to become part of the kernel
> selftests: This would mainly get the tests closer to the upstream kernel
> development, both in terms of maintenance and actually running them. CI
> systems like LKFT and CKI could easily be continuously running the
> tests.

Ok. Just for my understanding: Bringing the test cases into 
tools/testing/selftests would be the enabler to run LKFT and CKI, right?

Does it have any impact or improvement for syzbot or LTP too, e.g. that 
we can also improve their test quality?

> The downside is that existing automation depending on can-tests
> (which we don't know about) would need to be modified.

I don't know about any existing automation based in can-tests either.
The reason for the can-test was mostly to document my own PoCs when 
adding new features.

I have no objections to stay with this repo as a PoC playground that 
might also help developers to get inspirations - and start something new 
with the current code base which aims to fuel the kernel selftests.

> - Extend the coverage of the tests: This could include testing for,
> e.g., vcan, vxcan, and the cangw netlink interface. But we're open to
> feedback here if you see any pressing areas.

I see no pressing areas right now. But the recently integrated CAN XL 
support might get some attention ;-)

> Like I stated in the beginning, this message should get the discussion
> started and we are looking forward to your feedback or concerns on these
> ideas.

Many thanks Felix.

Best regards,
Oliver