On Thu, May 19, 2022, Vitaly Kuznetsov wrote: > This, however, made me think there's room for optimization here. In some > cases, when both KVM_REQ_TLB_FLUSH_CURRENT and KVM_REQ_TLB_FLUSH_GUEST > were requested, there's no need to flush twice, e.g. on SVM > .flush_tlb_current == .flush_tlb_guest. I'll probably not go into this > territory with this series as it's already fairly big, just something > for the future. Definitely not worth your time. On VMX, CURRENT isn't a superset of GUEST when EPT is enabled. And on SVM, the flush doesn't actually occur until VM-Enter, i.e. the redundant flush is just an extra write to svm->vmcb->control.tlb_ctl (or an extra decrement of asid_generation).
