> I'm asking about ucode/hardare. Is the "guest pebs buffer write -> PEBS PMI" > guaranteed to be atomic? Of course not. > > In practice, under what scenarios will guest counters get cross-mapped? And, > how does this support affect guest accuracy? I.e. how bad do things get for the > guest if we simply disable guest counters if they can't have a 1:1 association > with their physical counter? This would completely break perfmon for the guest, likely with no way to recover. -Andi
