On 17/07/20 14:52, Jon Doron wrote: > Based on an analysis of the HyperV firmwares (Gen1 and Gen2) it seems > like the SCONTROL is not being set to the ENABLED state as like we have > thought. > > Also from a test done by Vitaly Kuznetsov, running a nested HyperV it > was concluded that the first access to the SCONTROL MSR with a read > resulted with the value of 0x1, aka HV_SYNIC_CONTROL_ENABLE. > > It's important to note that this diverges from the value states in the > HyperV TLFS of 0. > > Signed-off-by: Jon Doron <arilou@xxxxxxxxx> > --- > arch/x86/kvm/hyperv.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c > index af9cdb426dd2..814d3aee5cef 100644 > --- a/arch/x86/kvm/hyperv.c > +++ b/arch/x86/kvm/hyperv.c > @@ -900,6 +900,7 @@ int kvm_hv_activate_synic(struct kvm_vcpu *vcpu, bool dont_zero_synic_pages) > kvm_request_apicv_update(vcpu->kvm, false, APICV_INHIBIT_REASON_HYPERV); > synic->active = true; > synic->dont_zero_synic_pages = dont_zero_synic_pages; > + synic->control = HV_SYNIC_CONTROL_ENABLE; > return 0; > } > > Applied, thanks! Paolo
