Re: crash on >= 4.9.0 kernel seems nf related

[Florian Westphal <fw@strlen.de>]

Bjørnar Ness <bjornar.ness@gmail.com> wrote:
> When trying to narrow down the problem, I removed the NAT rules, and
> in particular
> the
>
> chain postrouting {
>   type nat hook postrouting priority 100
> }
>
> And the problem disappears. Commenting in the above block again,
> causes the following to happen:
>
> kworker/0:0 starts to use more and more cpu, and in less than a minute
> renders the
> machine useless. If network cable is unplugged, it takes aroung 30
> seconds for the machine to get into a useful state again.

The kworker is most likely the conntrack gc worker, but the gc worker is nat
agnostic, so I don't see how this makes a difference wrt. nat
postrouting hook presence.

perf top might help pinpoint the source.

What kernel is this, exactly?

4.10 (and 4.9.14 and later) has a change to make gc worker use less
cycles.

But I don't see the NAT connection.