On Wed, May 22, 2024 at 8:11 AM Ravi Bangoria <ravi.bangoria@xxxxxxx> wrote: > >>> LBR Virtualization overhead for guest entry + exit roundtrip is ~450 cycles* on > >> > >> Ouch. Just to clearify, that's for LBR Stack Virtualization, correct? > > > > And they are all in the VMSA, triggered by LBR_CTL_ENABLE_MASK, for > > non SEV-ES guests? > > Not sure I follow. LBR_CTL_ENABLE_MASK works same for all types of guests. > Just that, it's mandatory for SEV-ES guests and optional for SVM and SEV > guests. I think you confirmed I mean: when you set LBR_CTL_ENABLE_MASK, you get the 450 cycle penalty because the whole set of LBR Stack MSRs is in the VMSA for both SVM/SEV guests (optional) and SEV-ES guests (mandatory). Paolo
