Re: [PATCH net-next v4 5/5] net: net_test: add tests for TCP re-segmentation

[Willem de Bruijn <willemdebruijn.kernel@gmail.com>]

Wang Zhan wrote:
> On Wed, 30 Sep 2026 15:53:09 -0400 Willem de Bruijn wrote:
> > Given that we have the above (concise) testcases: 
> >
> > Do we need to add the below verbose code? What does it add, just the
> > TCP specific path?
> 
> gso_test_tcp_resegment() is a v1 leftover, when tcp_gso_segment() needed a
> max_segs exception in its "untrusted source" check.  max_segs is passed
> through now, so it is unnecessary and can be dropped in v5.
> 
> gso_test_tcp_limit_l3_proto() was added in v3 for the L3 protocol limit
> lookup fix (1/5).
> 
> gso_test_tcp_resegment_l3_len() was added in v3 for the 64 KiB cap on the
> grouped output (4/5), from this sashiko report on v2:
> https://lore.kernel.org/179002380484.2160803.13955762820082413555@kernel.org/
> 
> You are right that they are verbose and one-off.  I do not have a concrete plan
> yet: I will try to trim them, or just drop them and add a selftest later.  Any
> suggestions?

The trade-off in added coverage vs added test code (that also has a
maintenance cost) is subjective.

I would maybe ask the LLM whether it can generate a significantly more
concise test that gives the same coverage. Initially they don't see to
optimize for size. It has worked for me before.

Otherwise, I'd drop 64KB limit test gso_test_tcp_resegment_l3_len, and
possibly both.

But as said subjective, your call.