Meltdown strikes back: the L1 terminal fault vulnerability

Keep in mind that "private clouds" often have real security concerns between their various workloads as well. When you're operating at significant scale you have a variety of problems. You have no idea what those various teams are doing, or what software they're running. They run at lot of third party software too, and no one has really analyzed it in every detail to know what it does.

This is mostly sane to do if you set policies that control what software can access what data, but this type of exploit is about circumventing that.

So I don't really see going private cloud as a solution for this type of problem.

You could go "non-converged" and isolate workloads, but I don't think that's on the cards.