Comment 89 for bug 997978

Packages are ready for testing in the all new ubuntu-virt/kvm-network-hang PPA.

It has a lower version than the test package Serge posted earlier, so you'll need to first disable that other PPA and then enable this one and upgrade.

This should do the trick:

# You can skip these first two commands if you didn't test Serge's packages earlier
sudo apt-get install ppa-purge
sudo ppa-purge -p backports ubuntu-virt

sudo add-apt-repository ppa:ubuntu-virt/kvm-network-hang
sudo apt-get update
sudo apt-get install qemu-kvm

Of course, use at your own risk, etc.