[Qemu-devel] Re: BUG - qdev - partial loss of network connectivity

[Leszek Urbanski <tygrys@moo.pl>]

<20100927213203.GA28089@moo.pl>; from Leszek Urbanski on Mon, Sep 27, 2010 at 23:32:03 +0200

> > > > >It's vanilla 2.6.32.22, but I also reproduced this on Debian's 2.6.32-23
> > > > >(based on 2.6.32.21).
> > > > >
> > > > >If offload is the only difference, I'll play with different offload
> > > > >options and check which one causes it.
> > > > >   
> > > > 
> > > > It's not technically the only difference but it's the most likely 
> > > > culprit IMHO.
> > > 
> > > udp fragmentation offload is definitely the culprit.
> > 
> > I see. Most likely guest bug - won't be the first bug around UFO.
> > If so pls copy netdev linux-nfs and virtualization.
> > Do you see anything in dmesg? Can try 2.6.36-rc5?
> 
> (for reference: first post is at:
> http://lists.nongnu.org/archive/html/qemu-devel/2010-09/msg01685.html )
> 
> I can't reproduce it on 2.6.36-rc5. Do you have an idea which patch may have

This one definitely fixes it: http://patchwork.ozlabs.org/patch/55643/

(Herbert Xu: udp: Fix bogus UFO packet generation)

The patch works with 2.6.32.24 too - it should probably be backported to
2.6.32.x.


-- 
Leszek "Tygrys" Urbanski, SCSA, SCNA
 "Unix-to-Unix Copy Program;" said PDP-1. "You will never find a more
  wretched hive of bugs and flamers. We must be cautious." -- DECWARS
     http://cygnus.moo.pl/ -- Cygnus High Altitude Balloon