Re: [PATCH net-next 0/5] net/sched: Retire some tc qdiscs and classifiers

[Jiri Pirko <jiri@resnulli.us>]

Tue, Feb 14, 2023 at 02:49:10PM CET, jhs@mojatatu.com wrote:
>The CBQ + dsmark qdiscs and the tcindex + rsvp classifiers have served us for
>over 2 decades. Unfortunately, they have not been getting much attention due
>to reduced usage. While we dont have a good metric for tabulating how much use
>a specific kernel feature gets, for these specific features we observed that
>some of the functionality has been broken for some time and no users complained.
>In addition, syzkaller has been going to town on most of these and finding
>issues; and while we have been fixing those issues, at times it becomes obvious
>that we would need to perform bigger surgeries to resolve things found while
>getting a syzkaller fix in place. After some discussion we feel that in order
>to reduce the maintenance burden it is best to retire them.
>
>This patchset leaves the UAPI alone. I could send another version which deletes
>the UAPI as well. AFAIK, this has not been done before - so it wasnt clear what
>how to handle UAPI. It seems legit to just delete it but we would need to
>coordinate with iproute2 (given they sync up with kernel uapi headers). There

I think we have to let the UAPI there to rot in order not to break
compilation of apps that use those (no relation to iproute2).


>are probably other users we don't know of that copy kernel headers.
>If folks feel differently I will resend the patches deleting UAPI for these
>qdiscs and classifiers.
>
>I will start another thread on iproute2 before sending any patches to iproute2.
>
>Jamal Hadi Salim (5):
>  net/sched: Retire CBQ qdisc
>  net/sched: Retire ATM qdisc
>  net/sched: Retire dsmark qdisc
>  net/sched: Retire tcindex classifier
>  net/sched: Retire rsvp classifier

set-
Acked-by: Jiri Pirko <jiri@nvidia.com>