Comment 0 for bug 1310586

Ubuntu 3.13.0-24.46-generic 3.13.9 seems to be affected by the same bug as described here: http://patchwork.ozlabs.org/patch/326048/

The suggested workaround (echo 0 > /sys/class/net/br0/bridge/multicast_snooping) solves IPv6-problems for KVM guests.