Re: [net-next v41] mctp pcc: Implement MCTP over PCC Transport

From: Jeremy Kerr

Date: Tue May 12 2026 - 00:08:27 EST


Hi Adam,

> Sorry, I should have been more explicit here.  I am not certain what is
> going to happen with fragmentation, so I want to be protected against
> future changes.

Nothing is going to happen with fragmentation. Your driver will only see
linear skbs in the ndo_start_xmit callback.

Adding the skb_linearize() there is unnecessary, and creates ambiguity
about the structure of the skbs that we're dealing with in that path.

> The check in validate_xmit_skb() is good, as it protects against the
> current set up. So my option was to put a comment in here and hope both
> changes happened together, or to just try and get this portion of the
> driver solid against the change.

I'm not clear on what changes you're referring to here?

> And I thought that was what you were suggesting in the comment. The
> original comment sounded more like an "here is an optimization" instead
> of "this is important enough to kick back"

It's less of an optimisation, and more removing something that is
unneeded, and potentially confusing ("why is the driver doing this?")?

> As for spacing, I get that there is a style, but it really should be
> encoded in checkstyle.sh or something and automated.  My own tendency is
> to put way too many spaces in to chunk things together, and I end up
> going over-draconian on stripping them out to try and meet the expected
> layout.

I'm not too fussed about the style at the level you have here, these are
suggestions to clean up if you're already re-rolling. My confusion is
that you had applied my feedback to one part of the code, but not to the
area I had commented on (which has the same style structure).

You also had some sashiko feedback on v40. I'm not sure whether all
items are relevant (I *think* you're OK for the first, for example), but
worth confirming:

https://sashiko.dev/#/patchset/20260508032953.337036-1-admiyo%40os.amperecomputing.com

Cheers,


Jeremy