xref: /linux/tools/testing/selftests/kvm/x86/hyperv_cpuid.c (revision 7f9039c524a351c684149ecf1b3c5145a0dff2fe)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Test for x86 KVM_CAP_HYPERV_CPUID
4  *
5  * Copyright (C) 2018, Red Hat, Inc.
6  *
7  * This work is licensed under the terms of the GNU GPL, version 2.
8  *
9  */
10 #include <fcntl.h>
11 #include <stdio.h>
12 #include <stdlib.h>
13 #include <string.h>
14 #include <sys/ioctl.h>
15 
16 #include "test_util.h"
17 #include "kvm_util.h"
18 #include "processor.h"
19 #include "vmx.h"
20 
21 static void guest_code(void)
22 {
23 }
24 
25 static void test_hv_cpuid(struct kvm_vcpu *vcpu, bool evmcs_expected)
26 {
27 	const bool has_irqchip = !vcpu || vcpu->vm->has_irqchip;
28 	const struct kvm_cpuid2 *hv_cpuid_entries;
29 	int i;
30 	int nent_expected = 10;
31 	u32 test_val;
32 
33 	if (vcpu)
34 		hv_cpuid_entries = vcpu_get_supported_hv_cpuid(vcpu);
35 	else
36 		hv_cpuid_entries = kvm_get_supported_hv_cpuid();
37 
38 	TEST_ASSERT(hv_cpuid_entries->nent == nent_expected,
39 		    "KVM_GET_SUPPORTED_HV_CPUID should return %d entries"
40 		    " (returned %d)",
41 		    nent_expected, hv_cpuid_entries->nent);
42 
43 	for (i = 0; i < hv_cpuid_entries->nent; i++) {
44 		const struct kvm_cpuid_entry2 *entry = &hv_cpuid_entries->entries[i];
45 
46 		TEST_ASSERT((entry->function >= 0x40000000) &&
47 			    (entry->function <= 0x40000082),
48 			    "function %x is our of supported range",
49 			    entry->function);
50 
51 		TEST_ASSERT(entry->index == 0,
52 			    ".index field should be zero");
53 
54 		TEST_ASSERT(entry->flags == 0,
55 			    ".flags field should be zero");
56 
57 		TEST_ASSERT(!entry->padding[0] && !entry->padding[1] &&
58 			    !entry->padding[2], "padding should be zero");
59 
60 		switch (entry->function) {
61 		case 0x40000000:
62 			test_val = 0x40000082;
63 
64 			TEST_ASSERT(entry->eax == test_val,
65 				    "Wrong max leaf report in 0x40000000.EAX: %x"
66 				    " (evmcs=%d)",
67 				    entry->eax, evmcs_expected
68 				);
69 			break;
70 		case 0x40000003:
71 			TEST_ASSERT(has_irqchip || !(entry->edx & BIT(19)),
72 				    "\"Direct\" Synthetic Timers should require in-kernel APIC");
73 			break;
74 		case 0x40000004:
75 			test_val = entry->eax & (1UL << 18);
76 
77 			TEST_ASSERT(!!test_val == !is_smt_possible(),
78 				    "NoNonArchitecturalCoreSharing bit"
79 				    " doesn't reflect SMT setting");
80 
81 			TEST_ASSERT(has_irqchip || !(entry->eax & BIT(10)),
82 				    "Cluster IPI (i.e. SEND_IPI) should require in-kernel APIC");
83 			break;
84 		case 0x4000000A:
85 			TEST_ASSERT(entry->eax & (1UL << 19),
86 				    "Enlightened MSR-Bitmap should always be supported"
87 				    " 0x40000000.EAX: %x", entry->eax);
88 			if (evmcs_expected)
89 				TEST_ASSERT((entry->eax & 0xffff) == 0x101,
90 				    "Supported Enlightened VMCS version range is supposed to be 1:1"
91 				    " 0x40000000.EAX: %x", entry->eax);
92 
93 			break;
94 		default:
95 			break;
96 
97 		}
98 		/*
99 		 * If needed for debug:
100 		 * fprintf(stdout,
101 		 *	"CPUID%lx EAX=0x%lx EBX=0x%lx ECX=0x%lx EDX=0x%lx\n",
102 		 *	entry->function, entry->eax, entry->ebx, entry->ecx,
103 		 *	entry->edx);
104 		 */
105 	}
106 
107 	/*
108 	 * Note, the CPUID array returned by the system-scoped helper is a one-
109 	 * time allocation, i.e. must not be freed.
110 	 */
111 	if (vcpu)
112 		free((void *)hv_cpuid_entries);
113 }
114 
115 static void test_hv_cpuid_e2big(struct kvm_vm *vm, struct kvm_vcpu *vcpu)
116 {
117 	static struct kvm_cpuid2 cpuid = {.nent = 0};
118 	int ret;
119 
120 	if (vcpu)
121 		ret = __vcpu_ioctl(vcpu, KVM_GET_SUPPORTED_HV_CPUID, &cpuid);
122 	else
123 		ret = __kvm_ioctl(vm->kvm_fd, KVM_GET_SUPPORTED_HV_CPUID, &cpuid);
124 
125 	TEST_ASSERT(ret == -1 && errno == E2BIG,
126 		    "%s KVM_GET_SUPPORTED_HV_CPUID didn't fail with -E2BIG when"
127 		    " it should have: %d %d", !vcpu ? "KVM" : "vCPU", ret, errno);
128 }
129 
130 int main(int argc, char *argv[])
131 {
132 	struct kvm_vm *vm;
133 	struct kvm_vcpu *vcpu;
134 
135 	TEST_REQUIRE(kvm_has_cap(KVM_CAP_HYPERV_CPUID));
136 
137 	/* Test the vCPU ioctl without an in-kernel local APIC. */
138 	vm = vm_create_barebones();
139 	vcpu = __vm_vcpu_add(vm, 0);
140 	test_hv_cpuid(vcpu, false);
141 	kvm_vm_free(vm);
142 
143 	/* Test vCPU ioctl version */
144 	vm = vm_create_with_one_vcpu(&vcpu, guest_code);
145 	test_hv_cpuid_e2big(vm, vcpu);
146 	test_hv_cpuid(vcpu, false);
147 
148 	if (!kvm_cpu_has(X86_FEATURE_VMX) ||
149 	    !kvm_has_cap(KVM_CAP_HYPERV_ENLIGHTENED_VMCS)) {
150 		print_skip("Enlightened VMCS is unsupported");
151 		goto do_sys;
152 	}
153 	vcpu_enable_evmcs(vcpu);
154 	test_hv_cpuid(vcpu, true);
155 
156 do_sys:
157 	/* Test system ioctl version */
158 	if (!kvm_has_cap(KVM_CAP_SYS_HYPERV_CPUID)) {
159 		print_skip("KVM_CAP_SYS_HYPERV_CPUID not supported");
160 		goto out;
161 	}
162 
163 	test_hv_cpuid_e2big(vm, NULL);
164 	test_hv_cpuid(NULL, kvm_cpu_has(X86_FEATURE_VMX));
165 
166 out:
167 	kvm_vm_free(vm);
168 
169 	return 0;
170 }
171