mvneta: oops in __rcu_read_lock on mirabox

[Ethan Tuttle]

On Mon, Sep 16, 2013 at 9:44 AM, Willy Tarreau <w at 1wt.eu> wrote:
> On Mon, Sep 16, 2013 at 06:39:37PM +0200, Willy Tarreau wrote:
>> On Mon, Sep 16, 2013 at 09:35:16AM -0700, Ethan Tuttle wrote:
>> > On Mon, Sep 16, 2013 at 8:51 AM, Thomas Petazzoni
>> > <thomas.petazzoni at free-electrons.com> wrote:
>> > > Willy, Ethan,
>> > >
>> > > On Mon, 16 Sep 2013 08:50:47 +0200, Willy Tarreau wrote:
>> > >
>> > >> I'm currently testing on 3.11.1 (which I had here) and am not getting
>> > >> any issue after 50M packets. My kernel is running in thumb mode and
>> > >> without SMP.
>> > >>
>> > >> Ethan, we'll need your config I guess.
>> > >
>> > > Can both of you also report the U-Boot version you're using, and the
>> > > SoC revision (it's visible in the U-Boot output).
>> >
>> > Mine says:
>> >
>> > U-Boot 2009.08 (Sep 16 2012 - 22:50:06)Marvell version: 1.1.2 NQ
>> > SoC:   MV6710 A1
>>
>> I just checked on my old captures and I have the same here, with more
>> details such as the CPU's revision (Rev 1) :
>>
>>    http://1wt.eu/articles/mirabox-vs-guruplug/
>
> BTW Ethan, I don't know if you have already opened your mirabox, but on the
> link above you'll find settings for trying other frequencies for the CPU. It
> could be nice to try 1 GHz with L2/DDR @500 instead of 1200/600 to see if the
> issue remains or not. If it disappears, there's also a working setting with
> CPU at 1.2G, L2 at 800M and DDR at 400M to help find if CPU, L2 or DDR is the culprit.
>
> Willy
>

I have not opened my mirabox - but sure, I'll open it up and try those
other settings when I get a chance.

Also, you mentioned that you have SMP disabled in your kernel.  It
looks like it's on in my .config.  Should I run a test with SMP
disabled?

I'm surprised that nobody else sees this crash given how easy it is
for me to reproduce.  BTW, the 3.11 kernel I made with 702821f
reverted has been humming along for days without issue.