Re: CAKE and r8169 cause panic on upload in v4.19

From: Dave Taht
Date: Fri Oct 26 2018 - 19:08:51 EST


On Fri, Oct 26, 2018 at 1:54 PM Oleksandr Natalenko
<oleksandr@xxxxxxxxxxxxxx> wrote:
>
> Hi.
>
> On 26.10.2018 22:25, Dave Taht wrote:
> > Can you repeat your test, disabling gro splitting in cake?
> >
> > the option is "no-split-gso"
>
> Still panics. Takes a couple of rounds, but panics.
>
> Moreover, I've stressed my HTB setup like this too for a longer time,
> and it panics as well. So, at least, now I have a proof this is not a
> CAKE-specific thing.

Groovy. :whew:

I do look forward to more cake test results, particularly on different
network cards such as these, and at speeds higher than 10Gbit on high
end hardware, and in the 100-1Gbit range on low to mid-range. After
the last round of features added to cake before it went into linux, we
run now out of cpu on inbound shaping at those speeds on low end apu2
(x86) hardware, (atom and a15 chips are not so hot now either) and I
wish I knew what we could do to speed it up. The new "list skb" and
mirred code looked promising but we haven't got around to exploring it
yet.

Thank you for trying and I hope this gets sorted out on your chipset.

>
> Also, I've stressed it even with noqueue, and the panic is still there.
> So, this thing is not even sch-specific.
>
> Next, I've seen GRO bits in the call trace and decided to disable GRO on
> this NIC. So far, I cannot trigger a panic with GRO disabled even after
> 20 rounds of speedtest.

We tend to use flent's rrul test to *really* abuse things. :)

So cake's ok with gro disabled in hw?

>
> So, must be some generic thing indeed.
>
> --
> Oleksandr Natalenko (post-factum)



--

Dave TÃht
CTO, TekLibre, LLC
http://www.teklibre.com
Tel: 1-831-205-9740