Re: [Qemu-devel] [BUG] Regression in networking code (SIGSEGV)

[Gleb Natapov <gleb@redhat.com>]

On Sun, Jan 25, 2009 at 10:29:38PM +0100, Stefan Weil wrote:
> Aurelien Jarno schrieb:
> > On Sat, Jan 24, 2009 at 10:00:33PM +0100, Stefan Weil wrote:
> >   
> >> Gleb Natapov schrieb:
> >>     
> >>> On Wed, Jan 21, 2009 at 10:17:20PM +0100, Stefan Weil wrote:
> >>>   
> >>>       
> >>>> Hi,
> >>>>
> >>>> the SIGSEGV crash below can be reproduced with Qemu r6391 and "high" net
> >>>> load.
> >>>>
> >>>> I bootet a mips malta kernel from a debian nfs root. While this worked fine,
> >>>> aptitude update hangs during downloads, nfs root is lost and after some time
> >>>> Qemu gets a SIGSEGV.
> >>>>
> >>>> A similar crash occurs with a different mips machine (ar7) and different
> >>>> network hardware (ar7 emac / cpmac), so it is not restricted to pcnet.
> >>>> This second system does not survive the network boot.
> >>>>
> >>>> Up to now, I could not run tests with non-mips systems.
> >>>>
> >>>> I'm fairly sure that 2 weeks ago networking worked without problems in both
> >>>> cases.
> >>>>
> >>>>     
> >>>>         
> >>> What is your host CPU?  How you run qemu (what is your command line)?
> >>>   
> >>>       
> >> Debian amd64 host.
> >>
> >> mipsel-softmmu/qemu-system-mipsel --kernel vmlinux \
> >>     --append "debug nohz=off root=/dev/nfs rw ip=::::malta-le::dhcp" \
> >>     -M malta --net nic --net user -m 256
> >>     
> >
> > The fact that your host system is 64-bit and you are using the user
> > networking is interesting. You could try to look at revisions 6272 and
> > 6288, they are probably the cause of your problem.
> >   
> 
> Yes, you are right. Reverting r6288 results in stable networking again.
> 
> Thank you for this hint.
> 
I also use amd64 host, but I was not able to reproduce this with other
guests. I'll try mips guest. Can you try to reproduce the problem with
different guest (x86 for instance)?


--
			Gleb.