Bug#603670: early kernel panic as node under kvm (div-by-zero in pvclock_tsc_khz)

[Moritz Muehlenhoff <jmm@inutil.org>]

On Thu, Nov 25, 2010 at 04:46:13PM +0000, Ben Hutchings wrote:
> On Tue, 2010-11-16 at 10:10 +0100, Stefan Bühler wrote: 
> > Package: linux-image-2.6.32-5-amd64
> > Version: 2.6.32-27
> > Severity: important
> > Found: linux-image-2.6.30-2-amd64/2.6.30-8squeeze1
> > Found: linux-image-2.6.36-trunk-amd64/2.6.36-1~experimental.1
> > 
> > Hi,
> > 
> > I get an early kernel panic when i try to run
> > testing/unstable/experimental kernels in a vm under kvm.
> > 
> > The physical host runs 2.6.32-5-amd64, and uses qemu-kvm/0.12.5+dfsg-4 
> > with libvirt 0.8.3-4.
> > 
> > The stable kernel does not panic: linux-image-2.6.26-2-amd64 2.6.26-25
> > 
> > Example log for 2.6.32-5-amd64 (experimental has similar backtrace); the
> > panic is caused by a div-by-zero in pvclock_tsc_khz here (v2.6.36 source):
> 
> I suspect that this is a bug in the host kernel's implementation of the
> pvclock (paravirtual clock), not the guest's use of it.  The kernel from
> stable works because it doesn't attempt to use the pvclock interface.
> Unfortunately really isn't enough information logged for me to tell for
> sure.
> 
> Could you test with Linux 2.6.36 in both host and guest?

Stefan, did you test with more recent kernels?

Cheers,
        Moritz