On 27/04/2018 00:28, Jim Mattson wrote: > The other thing that comes to mind is that there are some new fields > in the VMCS12 since I first implemented this. One potentially > troublesome field is the VMX preemption timer. If the current timer > value is not saved on VM-exit, then it won't be stashed in the shadow > VMCS12 by sync_vmcs12. Post-migration, the timer will be reset to its > original value. > > Do we care? Is this any different from what happens on real hardware > when there's an SMI? According to the SDM, this appears to be exacty > what happens when the dual-monitor treatment of SMIs and SMM is > active, but it's not clear what happens with the default treatment of > SMIs and SMM. I think it should be the same, because the preemption timer countdown is not part of the VMX-critical state. Paolo
