On 23/01/20 16:45, Sean Christopherson wrote: > cc'ing KVM and LKML this time... > > Why does KVM use the atomic load/store lists to load MSR_IA32_UMWAIT_CONTROL > on VM-Enter/VM-Exit? Unless the host kernel is doing UWMAIT, which it > really shouldn't and AFAICT doesn't, isn't it better to use the shared MSR > mechanism to load the host value only when returning to userspace, and > reload the guest value on demand? > To clarify, laziness also on part of the reviewer, aka me. Paolo