KVM: selftests: SEV-SNP test for KVM_SEV_INIT2

Add the X86_FEATURE_SEV_SNP CPU feature to the architectural definition
for the SEV-SNP VM type to exercise the KVM_SEV_INIT2 call. Ensure that
the SNP test is skipped in scenarios where CPUID supports it but KVM
does not, preventing reporting of failure in such cases.

Reviewed-by: Nikunj A Dadhania <nikunj@amd.com>
Signed-off-by: Pratik R. Sampat <prsampat@amd.com>
Link: https://lore.kernel.org/r/20250305230000.231025-3-prsampat@amd.com
[sean: use the same pattern as SEV and SEV-ES]
Signed-off-by: Sean Christopherson <seanjc@google.com>

diff --git a/tools/testing/selftests/kvm/include/x86/processor.h b/tools/testing/selftests/kvm/include/x86/processor.h
index 32ab6ca7ec3258cd9e32927faf285911e8755103..b11b5a53ebd59742d37018d4d222629ceaaceb08 100644 (file)
--- a/tools/testing/selftests/kvm/include/x86/processor.h
+++ b/tools/testing/selftests/kvm/include/x86/processor.h
@@ -203,6 +203,7 @@ struct kvm_x86_cpu_feature {
 #define X86_FEATURE_IDLE_HLT           KVM_X86_CPU_FEATURE(0x8000000A, 0, EDX, 30)
 #define X86_FEATURE_SEV                        KVM_X86_CPU_FEATURE(0x8000001F, 0, EAX, 1)
 #define X86_FEATURE_SEV_ES             KVM_X86_CPU_FEATURE(0x8000001F, 0, EAX, 3)
+#define X86_FEATURE_SEV_SNP            KVM_X86_CPU_FEATURE(0x8000001F, 0, EAX, 4)
 #define        X86_FEATURE_PERFMON_V2          KVM_X86_CPU_FEATURE(0x80000022, 0, EAX, 0)
 #define        X86_FEATURE_LBR_PMC_FREEZE      KVM_X86_CPU_FEATURE(0x80000022, 0, EAX, 2)
 

diff --git a/tools/testing/selftests/kvm/x86/sev_init2_tests.c b/tools/testing/selftests/kvm/x86/sev_init2_tests.c
index 3fb967f40c6a1626d1d2cff1032c0e2562c8a205..b238615196ade45bff848776878abfa46def0d1a 100644 (file)
--- a/tools/testing/selftests/kvm/x86/sev_init2_tests.c
+++ b/tools/testing/selftests/kvm/x86/sev_init2_tests.c
@@ -28,6 +28,7 @@
 int kvm_fd;
 u64 supported_vmsa_features;
 bool have_sev_es;
+bool have_snp;
 
 static int __sev_ioctl(int vm_fd, int cmd_id, void *data)
 {
@@ -83,6 +84,9 @@ void test_vm_types(void)
        if (have_sev_es)
                test_init2(KVM_X86_SEV_ES_VM, &(struct kvm_sev_init){});
 
+       if (have_snp)
+               test_init2(KVM_X86_SNP_VM, &(struct kvm_sev_init){});
+
        test_init2_invalid(0, &(struct kvm_sev_init){},
                           "VM type is KVM_X86_DEFAULT_VM");
        if (kvm_check_cap(KVM_CAP_VM_TYPES) & BIT(KVM_X86_SW_PROTECTED_VM))
@@ -138,15 +142,24 @@ int main(int argc, char *argv[])
                    "sev-es: KVM_CAP_VM_TYPES (%x) does not match cpuid (checking %x)",
                    kvm_check_cap(KVM_CAP_VM_TYPES), 1 << KVM_X86_SEV_ES_VM);
 
+       have_snp = kvm_cpu_has(X86_FEATURE_SEV_SNP);
+       TEST_ASSERT(have_snp == !!(kvm_check_cap(KVM_CAP_VM_TYPES) & BIT(KVM_X86_SNP_VM)),
+                   "sev-snp: KVM_CAP_VM_TYPES (%x) indicates SNP support (bit %d), but CPUID does not",
+                   kvm_check_cap(KVM_CAP_VM_TYPES), KVM_X86_SNP_VM);
+
        test_vm_types();
 
        test_flags(KVM_X86_SEV_VM);
        if (have_sev_es)
                test_flags(KVM_X86_SEV_ES_VM);
+       if (have_snp)
+               test_flags(KVM_X86_SNP_VM);
 
        test_features(KVM_X86_SEV_VM, 0);
        if (have_sev_es)
                test_features(KVM_X86_SEV_ES_VM, supported_vmsa_features);
+       if (have_snp)
+               test_features(KVM_X86_SNP_VM, supported_vmsa_features);
 
        return 0;
 }