On Fri, 2019-10-04 at 09:24 +0200, Paolo Bonzini wrote:
> On 03/10/19 23:23, Rick Edgecombe wrote:
> > Add a KVM capability for the KVM_MEM_EXECONLY memslot type. This memslot
> > type is supported if the HW supports execute-only TDP.
> >
> > Signed-off-by: Rick Edgecombe <rick.p.edgecombe@xxxxxxxxx>
> > ---
> > arch/x86/include/asm/kvm_host.h | 1 +
> > arch/x86/kvm/svm.c | 6 ++++++
> > arch/x86/kvm/vmx/vmx.c | 1 +
> > arch/x86/kvm/x86.c | 3 +++
> > include/uapi/linux/kvm.h | 1 +
> > 5 files changed, 12 insertions(+)
> >
> > diff --git a/arch/x86/include/asm/kvm_host.h
> > b/arch/x86/include/asm/kvm_host.h
> > index 6d06c794d720..be3ff71e6227 100644
> > --- a/arch/x86/include/asm/kvm_host.h
> > +++ b/arch/x86/include/asm/kvm_host.h
> > @@ -1132,6 +1132,7 @@ struct kvm_x86_ops {
> > bool (*xsaves_supported)(void);
> > bool (*umip_emulated)(void);
> > bool (*pt_supported)(void);
> > + bool (*tdp_xo_supported)(void);
> >
> > int (*check_nested_events)(struct kvm_vcpu *vcpu, bool external_intr);
> > void (*request_immediate_exit)(struct kvm_vcpu *vcpu);
> > diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
> > index e0368076a1ef..f9f25f32e946 100644
> > --- a/arch/x86/kvm/svm.c
> > +++ b/arch/x86/kvm/svm.c
> > @@ -6005,6 +6005,11 @@ static bool svm_pt_supported(void)
> > return false;
> > }
> >
> > +static bool svm_xo_supported(void)
> > +{
> > + return false;
> > +}
> > +
> > static bool svm_has_wbinvd_exit(void)
> > {
> > return true;
> > @@ -7293,6 +7298,7 @@ static struct kvm_x86_ops svm_x86_ops __ro_after_init
> > = {
> > .xsaves_supported = svm_xsaves_supported,
> > .umip_emulated = svm_umip_emulated,
> > .pt_supported = svm_pt_supported,
> > + .tdp_xo_supported = svm_xo_supported,
> >
> > .set_supported_cpuid = svm_set_supported_cpuid,
> >
> > diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
> > index a30dbab8a2d4..7e7260c715f2 100644
> > --- a/arch/x86/kvm/vmx/vmx.c
> > +++ b/arch/x86/kvm/vmx/vmx.c
> > @@ -7767,6 +7767,7 @@ static struct kvm_x86_ops vmx_x86_ops __ro_after_init
> > = {
> > .xsaves_supported = vmx_xsaves_supported,
> > .umip_emulated = vmx_umip_emulated,
> > .pt_supported = vmx_pt_supported,
> > + .tdp_xo_supported = cpu_has_vmx_ept_execute_only,
> >
> > .request_immediate_exit = vmx_request_immediate_exit,
> >
> > diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
> > index 2e321d788672..810cfdb1a315 100644
> > --- a/arch/x86/kvm/x86.c
> > +++ b/arch/x86/kvm/x86.c
> > @@ -3183,6 +3183,9 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long
> > ext)
> > r = kvm_x86_ops->get_nested_state ?
> > kvm_x86_ops->get_nested_state(NULL, NULL, 0) : 0;
> > break;
> > + case KVM_CAP_EXECONLY_MEM:
> > + r = kvm_x86_ops->tdp_xo_supported();
> > + break;
> > default:
> > break;
> > }
> > diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
> > index ede487b7b216..7778a1f03b78 100644
> > --- a/include/uapi/linux/kvm.h
> > +++ b/include/uapi/linux/kvm.h
> > @@ -997,6 +997,7 @@ struct kvm_ppc_resize_hpt {
> > #define KVM_CAP_ARM_PTRAUTH_ADDRESS 171
> > #define KVM_CAP_ARM_PTRAUTH_GENERIC 172
> > #define KVM_CAP_PMU_EVENT_FILTER 173
> > +#define KVM_CAP_EXECONLY_MEM 174
> >
> > #ifdef KVM_CAP_IRQ_ROUTING
> >
> >
>
> This is not needed, execution only can be a CPUID bit in the hypervisor
> range (see Documentation/virt/kvm/cpuid.txt). Userspace can use
> KVM_GET_SUPPORTED_CPUID to check whether the host supports it.
>
Oh yea. I didn't see this. Definitely seems better.
Thanks,
Rick
