[PATCH 2/3] KVM: eVMCS: check if nesting is enabled

From: Paolo Bonzini
Date: Fri Apr 17 2020 - 12:44:32 EST


In the next patch nested_get_evmcs_version will be always set in kvm_x86_ops for
VMX, even if nesting is disabled. Therefore, check whether VMX (aka nesting)
is available in the function, the caller will not do the check anymore.

Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
---
arch/x86/kvm/vmx/evmcs.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kvm/vmx/evmcs.c b/arch/x86/kvm/vmx/evmcs.c
index 73f3e07c1852..48dc77de9337 100644
--- a/arch/x86/kvm/vmx/evmcs.c
+++ b/arch/x86/kvm/vmx/evmcs.c
@@ -4,6 +4,7 @@
#include <linux/smp.h>

#include "../hyperv.h"
+#include "../cpuid.h"
#include "evmcs.h"
#include "vmcs.h"
#include "vmx.h"
@@ -333,7 +334,8 @@ uint16_t nested_get_evmcs_version(struct kvm_vcpu *vcpu)
* maximum supported version. KVM supports versions from 1 to
* KVM_EVMCS_VERSION.
*/
- if (vmx->nested.enlightened_vmcs_enabled)
+ if (kvm_cpu_cap_get(X86_FEATURE_VMX) &&
+ vmx->nested.enlightened_vmcs_enabled)
return (KVM_EVMCS_VERSION << 8) | 1;

return 0;
--
2.18.2