From 225b7c1117b2f6dadbdb1d40538d37b9685e8b18 Mon Sep 17 00:00:00 2001 From: Vitaly Kuznetsov Date: Tue, 5 Dec 2023 11:36:24 +0100 Subject: KVM: selftests: Fix vmxon_pa == vmcs12_pa == -1ull nVMX testcase for !eVMCS The "vmxon_pa == vmcs12_pa == -1ull" test happens to work by accident: as Enlightened VMCS is always supported, set_default_vmx_state() adds 'KVM_STATE_NESTED_EVMCS' to 'flags' and the following branch of vmx_set_nested_state() is executed: if ((kvm_state->flags & KVM_STATE_NESTED_EVMCS) && (!guest_can_use(vcpu, X86_FEATURE_VMX) || !vmx->nested.enlightened_vmcs_enabled)) return -EINVAL; as 'enlightened_vmcs_enabled' is false. In fact, "vmxon_pa == vmcs12_pa == -1ull" is a valid state when not tainted by wrong flags so the test should aim for this branch: if (kvm_state->hdr.vmx.vmxon_pa == INVALID_GPA) return 0; Test all this properly: - Without KVM_STATE_NESTED_EVMCS in the flags, the expected return value is '0'. - With KVM_STATE_NESTED_EVMCS flag (when supported) set, the expected return value is '-EINVAL' prior to enabling eVMCS and '0' after. Reviewed-by: Maxim Levitsky Tested-by: Jeremi Piotrowski Signed-off-by: Vitaly Kuznetsov Link: https://lore.kernel.org/r/20231205103630.1391318-11-vkuznets@redhat.com Signed-off-by: Sean Christopherson --- .../selftests/kvm/x86_64/vmx_set_nested_state_test.c | 16 ++++++++++------ 1 file changed, 10 insertions(+), 6 deletions(-) (limited to 'tools/testing/selftests/kvm') diff --git a/tools/testing/selftests/kvm/x86_64/vmx_set_nested_state_test.c b/tools/testing/selftests/kvm/x86_64/vmx_set_nested_state_test.c index 41ea7028a1f8..67a62a5a8895 100644 --- a/tools/testing/selftests/kvm/x86_64/vmx_set_nested_state_test.c +++ b/tools/testing/selftests/kvm/x86_64/vmx_set_nested_state_test.c @@ -125,21 +125,25 @@ void test_vmx_nested_state(struct kvm_vcpu *vcpu) /* * Setting vmxon_pa == -1ull and vmcs_pa == -1ull exits early without - * setting the nested state but flags other than eVMCS must be clear. - * The eVMCS flag can be set if the enlightened VMCS capability has - * been enabled. + * setting the nested state. When the eVMCS flag is not set, the + * expected return value is '0'. */ set_default_vmx_state(state, state_sz); + state->flags = 0; state->hdr.vmx.vmxon_pa = -1ull; state->hdr.vmx.vmcs12_pa = -1ull; - test_nested_state_expect_einval(vcpu, state); + test_nested_state(vcpu, state); - state->flags &= KVM_STATE_NESTED_EVMCS; + /* + * When eVMCS is supported, the eVMCS flag can only be set if the + * enlightened VMCS capability has been enabled. + */ if (have_evmcs) { + state->flags = KVM_STATE_NESTED_EVMCS; test_nested_state_expect_einval(vcpu, state); vcpu_enable_evmcs(vcpu); + test_nested_state(vcpu, state); } - test_nested_state(vcpu, state); /* It is invalid to have vmxon_pa == -1ull and SMM flags non-zero. */ state->hdr.vmx.smm.flags = 1; -- cgit v1.2.3