KVM: selftests: update hyperv_cpuid with SynDBG tests

Update tests to reflect new CPUID capabilities with SYNDBG.
Check that we get the right number of entries and that
0x40000000.EAX always returns the correct max leaf.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Jon Doron <arilou@gmail.com>
Message-Id: <20200529134543.1127440-7-arilou@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

tools/testing/selftests/kvm/x86_64/hyperv_cpuid.c

@@ -26,18 +26,18 @@ static void guest_code(void)
 {
 }
 
-static int smt_possible(void)
+static bool smt_possible(void)
 {
 	char buf[16];
 	FILE *f;
-	bool res = 1;
+	bool res = true;
 
 	f = fopen("/sys/devices/system/cpu/smt/control", "r");
 	if (f) {
 		if (fread(buf, sizeof(*buf), sizeof(buf), f) > 0) {
 			if (!strncmp(buf, "forceoff", 8) ||
 			    !strncmp(buf, "notsupported", 12))
-				res = 0;
+				res = false;
 		}
 		fclose(f);
 	}
@@ -46,29 +46,31 @@ static int smt_possible(void)
 }
 
 static void test_hv_cpuid(struct kvm_cpuid2 *hv_cpuid_entries,
-			  int evmcs_enabled)
+			  bool evmcs_enabled)
 {
 	int i;
+	int nent = 9;
+	u32 test_val;
 
-	if (!evmcs_enabled)
-		TEST_ASSERT(hv_cpuid_entries->nent == 6,
-			    "KVM_GET_SUPPORTED_HV_CPUID should return 6 entries"
-			    " when Enlightened VMCS is disabled (returned %d)",
-			    hv_cpuid_entries->nent);
-	else
-		TEST_ASSERT(hv_cpuid_entries->nent == 7,
-			    "KVM_GET_SUPPORTED_HV_CPUID should return 7 entries"
-			    " when Enlightened VMCS is enabled (returned %d)",
-			    hv_cpuid_entries->nent);
+	if (evmcs_enabled)
+		nent += 1; /* 0x4000000A */
+
+	TEST_ASSERT(hv_cpuid_entries->nent == nent,
+		    "KVM_GET_SUPPORTED_HV_CPUID should return %d entries"
+		    " with evmcs=%d (returned %d)",
+		    nent, evmcs_enabled, hv_cpuid_entries->nent);
 
 	for (i = 0; i < hv_cpuid_entries->nent; i++) {
 		struct kvm_cpuid_entry2 *entry = &hv_cpuid_entries->entries[i];
 
 		TEST_ASSERT((entry->function >= 0x40000000) &&
-			    (entry->function <= 0x4000000A),
+			    (entry->function <= 0x40000082),
 			    "function %x is our of supported range",
 			    entry->function);
 
+		TEST_ASSERT(evmcs_enabled || (entry->function != 0x4000000A),
+			    "0x4000000A leaf should not be reported");
+
 		TEST_ASSERT(entry->index == 0,
 			    ".index field should be zero");
 
@@ -78,12 +80,23 @@ static void test_hv_cpuid(struct kvm_cpuid2 *hv_cpuid_entries,
 		TEST_ASSERT(!entry->padding[0] && !entry->padding[1] &&
 			    !entry->padding[2], "padding should be zero");
 
-		if (entry->function == 0x40000004) {
-			int nononarchcs = !!(entry->eax & (1UL << 18));
+		switch (entry->function) {
+		case 0x40000000:
+			test_val = 0x40000082;
+
+			TEST_ASSERT(entry->eax == test_val,
+				    "Wrong max leaf report in 0x40000000.EAX: %x"
+				    " (evmcs=%d)",
+				    entry->eax, evmcs_enabled
+				);
+			break;
+		case 0x40000004:
+			test_val = entry->eax & (1UL << 18);
 
-			TEST_ASSERT(nononarchcs == !smt_possible(),
+			TEST_ASSERT(!!test_val == !smt_possible(),
 				    "NoNonArchitecturalCoreSharing bit"
 				    " doesn't reflect SMT setting");
+			break;
 		}
 
 		/*
@@ -133,8 +146,9 @@ struct kvm_cpuid2 *kvm_get_supported_hv_cpuid(struct kvm_vm *vm)
 int main(int argc, char *argv[])
 {
 	struct kvm_vm *vm;
-	int rv;
+	int rv, stage;
 	struct kvm_cpuid2 *hv_cpuid_entries;
+	bool evmcs_enabled;
 
 	/* Tell stdout not to buffer its content */
 	setbuf(stdout, NULL);
@@ -145,36 +159,31 @@ int main(int argc, char *argv[])
 		exit(KSFT_SKIP);
 	}
 
-	/* Create VM */
-	vm = vm_create_default(VCPU_ID, 0, guest_code);
+	for (stage = 0; stage < 3; stage++) {
+		evmcs_enabled = false;
 
+		vm = vm_create_default(VCPU_ID, 0, guest_code);
+		switch (stage) {
+		case 0:
 			test_hv_cpuid_e2big(vm);
-
-	hv_cpuid_entries = kvm_get_supported_hv_cpuid(vm);
-	if (!hv_cpuid_entries)
-		return 1;
-
-	test_hv_cpuid(hv_cpuid_entries, 0);
-
-	free(hv_cpuid_entries);
-
+			continue;
+		case 1:
+			break;
+		case 2:
 			if (!kvm_check_cap(KVM_CAP_HYPERV_ENLIGHTENED_VMCS)) {
 				print_skip("Enlightened VMCS is unsupported");
-		goto vm_free;
+				continue;
 			}
-
 			vcpu_enable_evmcs(vm, VCPU_ID);
+			evmcs_enabled = true;
+			break;
+		}
 
 		hv_cpuid_entries = kvm_get_supported_hv_cpuid(vm);
-	if (!hv_cpuid_entries)
-		return 1;
-
-	test_hv_cpuid(hv_cpuid_entries, 1);
-
+		test_hv_cpuid(hv_cpuid_entries, evmcs_enabled);
 		free(hv_cpuid_entries);
-
-vm_free:
 		kvm_vm_free(vm);
+	}
 
 	return 0;
 }