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

[Michael S. Tsirkin]

On Thu, Sep 23, 2010 at 04:04:37PM +0200, Leszek Urbanski wrote:
> <address@hidden>; from Anthony Liguori on Wed, Sep 22, 2010 at 13:35:35 -0500
> 
> > >>Is the guest kernel vanilla 2.6.32.22 or is it a distro kernel?  If the
> > >>later, what distro?
> > >>
> > >>The difference in the two invocations is that with the -device syntax,
> > >>you're getting offload features enabled.
> > >>     
> > >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?



> -- 
> 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