Re: [PATCH net] net/sched: Avoid quadratic handle scan in qdisc_alloc_handle

On Tue, Sep 15, 2026 at 4:51 AM Jamal Hadi Salim [off-list ref] wrote:

On Mon, Sep 14, 2026 at 10:11 PM Jakub Kicinski [off-list ref] wrote:

quoted

On Fri, 11 Sep 2026 10:31:46 -0300 Victor Nogueira wrote:

quoted

This is a less intrusive fix meant for backporting; a cleaner approach that
uses a per-device IDA over all qdisc handles is planned for net-next.

I don't think this is net-worthy in the first place.
We have a ton of code under rtnl_lock.
We cannot provide any protection from malicious netns admin from
overloading the machine.

That is the one million dollar question.  We labelled this as net for
this exact reason. i.e malicious container could overload the whole
machine.
But it borders on "hardening" (improves performance), so net-next as a
target sounds reasonable. It was a coin toss.

Since we have a few similar "grey" issues in our pending queue - so
where's the line for net/net-next?

quoted

Nothing against the patch itself, but if you plan to do something
else in net-next let's just go with that from the start..

We could resend the same patch for net-next, the alternative "proper
fix" is more intrusive. See attached.
Another option: Is this worth fixing?

A really useful fix would be to get away from RTNL :)