On Tue, Apr 20, 2021 at 05:35:01PM +0000, Sean Christopherson wrote:
> On Fri, Apr 09, 2021, Yang Weijiang wrote:
> > These fields are rarely updated by L1 QEMU/KVM, sync them when L1 is trying to
> > read/write them and after they're changed. If CET guest entry-load bit is not
> > set by L1 guest, migrate them to L2 manaully.
> >
> > Opportunistically remove one blank line in previous patch.
> >
> > Suggested-by: Sean Christopherson <seanjc@xxxxxxxxxx>
> > Signed-off-by: Yang Weijiang <weijiang.yang@xxxxxxxxx>
> > ---
> > arch/x86/kvm/cpuid.c | 1 -
> > arch/x86/kvm/vmx/nested.c | 30 ++++++++++++++++++++++++++++++
> > arch/x86/kvm/vmx/vmx.h | 3 +++
> > 3 files changed, 33 insertions(+), 1 deletion(-)
> >
> > vmx_set_rflags(vcpu, vmcs12->guest_rflags);
> >
> > /* EXCEPTION_BITMAP and CR0_GUEST_HOST_MASK should basically be the
> > @@ -3375,6 +3391,11 @@ enum nvmx_vmentry_status nested_vmx_enter_non_root_mode(struct kvm_vcpu *vcpu,
> > if (kvm_mpx_supported() &&
> > !(vmcs12->vm_entry_controls & VM_ENTRY_LOAD_BNDCFGS))
> > vmx->nested.vmcs01_guest_bndcfgs = vmcs_read64(GUEST_BNDCFGS);
> > + if (kvm_cet_supported() && !vmx->nested.nested_run_pending) {
>
> This needs to be:
>
> if (kvm_cet_supported() && (!vmx->nested.nested_run_pending ||
> !(vmcs12->vm_entry_controls & VM_ENTRY_LOAD_CET_STATE)))
>
> otherwise the vmcs01_* members will be stale when emulating VM-Enter with
> vcmc12.vm_entry_controls.LOAD_CET_STATE=0.
>
Thanks Sean! Change is included in v6 patch series.
> > + vmx->nested.vmcs01_guest_ssp = vmcs_readl(GUEST_SSP);
> > + vmx->nested.vmcs01_guest_s_cet = vmcs_readl(GUEST_S_CET);
> > + vmx->nested.vmcs01_guest_ssp_tbl = vmcs_readl(GUEST_INTR_SSP_TABLE);
> > + }
