[PATCH v4 3/3] KVM: nVMX: Add CET entry/exit load bits to evmcs unsupported list

Yang Weijiang
2021-03-15T07:07:59Z

Nested guest doesn't support CET when KVM is running as an intermediate
layer between two Hyper-Vs for now, so mask out related CET entry/exit
load bits. Relevant enabling patches will be posted as a separate patch
series.

Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Suggested-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Yang Weijiang <weijiang.yang@intel.com>
---
arch/x86/kvm/vmx/evmcs.c | 4 ++--
arch/x86/kvm/vmx/evmcs.h | 6 ++++--
2 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/arch/x86/kvm/vmx/evmcs.c b/arch/x86/kvm/vmx/evmcs.c
index 41f24661af04..9f81db51fd8b 100644
--- a/arch/x86/kvm/vmx/evmcs.c
+++ b/arch/x86/kvm/vmx/evmcs.c
@@ -351,11 +351,11 @@ void nested_evmcs_filter_control_msr(u32 msr_index, u64 *pdata)
switch (msr_index) {
case MSR_IA32_VMX_EXIT_CTLS:
case MSR_IA32_VMX_TRUE_EXIT_CTLS:
- ctl_high &= ~VM_EXIT_LOAD_IA32_PERF_GLOBAL_CTRL;
+ ctl_high &= ~EVMCS1_UNSUPPORTED_VMEXIT_CTRL;
break;
case MSR_IA32_VMX_ENTRY_CTLS:
case MSR_IA32_VMX_TRUE_ENTRY_CTLS:
- ctl_high &= ~VM_ENTRY_LOAD_IA32_PERF_GLOBAL_CTRL;
+ ctl_high &= ~EVMCS1_UNSUPPORTED_VMENTRY_CTRL;
break;
case MSR_IA32_VMX_PROCBASED_CTLS2:
ctl_high &= ~SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES;
diff --git a/arch/x86/kvm/vmx/evmcs.h b/arch/x86/kvm/vmx/evmcs.h
index bd41d9462355..25588694eb04 100644
--- a/arch/x86/kvm/vmx/evmcs.h
+++ b/arch/x86/kvm/vmx/evmcs.h
@@ -59,8 +59,10 @@ DECLARE_STATIC_KEY_FALSE(enable_evmcs);
SECONDARY_EXEC_SHADOW_VMCS | \
SECONDARY_EXEC_TSC_SCALING | \
SECONDARY_EXEC_PAUSE_LOOP_EXITING)
-#define EVMCS1_UNSUPPORTED_VMEXIT_CTRL (VM_EXIT_LOAD_IA32_PERF_GLOBAL_CTRL)
-#define EVMCS1_UNSUPPORTED_VMENTRY_CTRL (VM_ENTRY_LOAD_IA32_PERF_GLOBAL_CTRL)
+#define EVMCS1_UNSUPPORTED_VMEXIT_CTRL (VM_EXIT_LOAD_IA32_PERF_GLOBAL_CTRL | \
+ VM_EXIT_LOAD_CET_STATE)
+#define EVMCS1_UNSUPPORTED_VMENTRY_CTRL (VM_ENTRY_LOAD_IA32_PERF_GLOBAL_CTRL | \
+ VM_ENTRY_LOAD_CET_STATE)
#define EVMCS1_UNSUPPORTED_VMFUNC (VMX_VMFUNC_EPTP_SWITCHING)

#if IS_ENABLED(CONFIG_HYPERV)
--
2.26.2