Bug#716696: linux-image-3.9-1-amd64: 3.9.8-1 freezes when libvirt/KVM guest VM attempts network I/O with virtio adapter

[C W <commparse@gmail.com>]

On Sat, Aug 3, 2013 at 11:25 AM, Ben Hutchings <ben@decadent.org.uk> wrote:

Control: tag -1 security moreinfo

On Thu, 2013-07-11 at 10:09 -0400, C W wrote:
> Package: src:linux
> Version: 3.9.8-1
> Severity: critical
> Justification: breaks the whole system

Sorry for the slow response, I don't why this was missed.

 No problem.  If anyone else has this problem, they can see it has a simple workaround.

> Dear Maintainer,
>
> 3.9.8-1 freezes the host when an Ubuntu 12.04 32-bit or 64-bit guest VM using
> libvirt/KVM attempts to go through the virtual network bridge using the virtio
> adapter.  This freeze is reproducible 100% of the time.  The guest is using the
> default libvirt network setup (NAT'ed with the virtual bridge virbr0, virtio
> network adapter) so nothing is strange there.  I have not yet seen a panic.
>
> This issue is not present with the previous version of linux-image-3.9-1:
> 3.9.6-1

[...]

I don't see any changes between these two versions that seem like they
could have caused this.  Have you verified this by downgrading to
3.9.6-1?

The bug does not appear to be in 3.9.6-1.

 

Is the bug still present in 3.10.3-1, currently in unstable?

The bug *also* does not appear to be in 3.10.3-1, which is good news.

I also tested an Ubuntu 13.04 VM -- to see if perhaps it was some strange interaction between the host and guest virtio drivers.  13.04 locked up just the same.  So, if the host is Debian 3.9.8-1 and the guest is either Ubuntu 12.04 (linux-image-3.2.0-37-generic) or 13.04 (linux-image-3.8.0-27-generic), the virtio NIC will freeze the host.