Xen has a smaller TCB only if you consider Dom0 not part of the TCB. But since a compromised Dom0 would lead to the compromise of the whole system, I think it m

Xen has a smaller TCB only if you consider Dom0 not part of the TCB. But since a compromised Dom0 would lead to the compromise of the whole system, I think it makes more sense to view Dom0 as part of the TCB.