Can't move to KVM because it uses v4 kernel
Any one know how to build a custom kernel for KVM? We have no idea where to start with it, since we don't know what needs to be built into it to work in the Linode environment – that's why we've always used the Linode-provided kernels.
That said, you do have more flexibility to run custom environments with KVM. Depending on what distribution you're running, you might want to try using their stock kernel and it could just work. You can also try switching to full virtualization mode.
In any case, thanks very much for the information – this gives us a good place to start.