Install ethtool and Disable the GRO, GSO.

Depending on your network interface driver, you may need to disable
Generic Receive Offload (GRO) to achieve suitable throughtput between
your instances and external network.

Reference:
https://ask.openstack.org/en/question/29147/ssh-to-a-vm-causes-kernel-panic-on-icehouse-neutron-host/