Re: [Bugme-new] [Bug 16626] New: Machine hangs with EIP at skb_copy_and_csum_dev

[Eric Dumazet <eric.dumazet@gmail.com>]

Le vendredi 20 août 2010 à 12:19 +0300, Plamen Petrov a écrit :
> На 20.8.2010 г. 11:31, Plamen Petrov написа:
> ...
> > The next thing I will be trying is disabling
> > GRO for the tg3 network card in my network
> > startup scripts via my shiny new ethtool... ;)
> 
> So, for nearly half an hour now running 2.6.36-rc1-FS-00127-g763008c:
> 
> >
> root@fs:~# w; uname -a
> >  12:09:48 up 26 min,  1 user,  load average: 2.43, 1.93, 1.26
> > USER     TTY      FROM              LOGIN@   IDLE   JCPU   PCPU WHAT
> > root     pts/0    192.168.10.159   12:09    0.00s  0.02s  0.00s w
> > Linux fs 2.6.36-rc1-FS-00127-g763008c #1 SMP Thu Aug 19 07:10:57 UTC 2010 i686 Intel(R) Pentium(R) D CPU 3.00GHz GenuineIntel GNU/Linux
> 
> And that's with the usual load, which can be found here:
> http://pvp.now.im/s/drraw.cgi?Mode=view;Dashboard=1173713287.13177
> 
> The only addition I made was running
> 	ethtool -K ethX gro off
> for each network card.
> 
> Which means that I have a Broadcom Tygon 3 (tg3) which doesn't
> like "generic-receive-offload" at all!
> 
> With "generic-receive-offload" off, I will stay on
> 2.6.36-rc1-FS-00127-g763008c for as long as I can, just to
> confirm that in fact the "default on" setting for gro in the
> tg3 driver is the culprit for my troubles...
> 
> Where to next?


First, thanks a lot for finding this so fast.

Hmmm, please check that on your net/core/dev.c file, line 3146 you have
the fix added in 

http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=e5093aec2e6b60c3df2420057ffab9ed4a6d2792

commit e5093aec2e6b60c3df2420057ffab9ed4a6d2792
Author: Jarek Poplawski <jarkao2@gmail.com>
Date:   Wed Aug 11 02:02:10 2010 +0000

    net: Fix a memmove bug in dev_gro_receive()
    


	--skb_shinfo(skb)->nr_frags * sizeof(skb_frag_t));



If yes, I think David & Herbert will probably have to dig again into gro
code :(