On 07/07/20 13:35, Maxim Levitsky wrote: > After thinking about this, I am thinking that we should apply similiar logic > as done with the 'cpu-pm' related features. > This way the user can choose between passing through the IA32_SPEC_CTRL, > (and in this case, we can since the user choose it, pass it right away, and thus > avoid using kvm_spec_ctrl_valid_bits completely), and between correctness, > in which case we can always emulate this msr, and therefore check all the bits, > both regard to guest and host supported values. Unfortunately, passing it through is just too slow. So I think it's overkill. There's two ways to deal with badly-behaved guests blocking migration: 1) hide SPEC_CTRL altogether 2) kill them when migration fails; both are acceptable depending on the situation. Paolo > Does this makes sense, or do you think that this is overkill?
