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 
11 #define _GNU_SOURCE /* for program_invocation_short_name */
12 #include <fcntl.h>
13 #include <stdio.h>
14 #include <stdlib.h>
15 #include <string.h>
16 #include <sys/ioctl.h>
17 
18 #include "test_util.h"
19 #include "kvm_util.h"
20 #include "processor.h"
21 
22 #define VCPU_ID 0
23 
24 static void guest_code(void)
25 {
26 }
27 
28 static void test_hv_cpuid(struct kvm_cpuid2 *hv_cpuid_entries,
29 			  int evmcs_enabled)
30 {
31 	int i;
32 
33 	if (!evmcs_enabled)
34 		TEST_ASSERT(hv_cpuid_entries->nent == 6,
35 			    "KVM_GET_SUPPORTED_HV_CPUID should return 6 entries"
36 			    " when Enlightened VMCS is disabled (returned %d)",
37 			    hv_cpuid_entries->nent);
38 	else
39 		TEST_ASSERT(hv_cpuid_entries->nent == 7,
40 			    "KVM_GET_SUPPORTED_HV_CPUID should return 7 entries"
41 			    " when Enlightened VMCS is enabled (returned %d)",
42 			    hv_cpuid_entries->nent);
43 
44 	for (i = 0; i < hv_cpuid_entries->nent; i++) {
45 		struct kvm_cpuid_entry2 *entry = &hv_cpuid_entries->entries[i];
46 
47 		TEST_ASSERT((entry->function >= 0x40000000) &&
48 			    (entry->function <= 0x4000000A),
49 			    "function %lx is our of supported range",
50 			    entry->function);
51 
52 		TEST_ASSERT(entry->index == 0,
53 			    ".index field should be zero");
54 
55 		TEST_ASSERT(entry->flags == 0,
56 			    ".flags field should be zero");
57 
58 		TEST_ASSERT(!entry->padding[0] && !entry->padding[1] &&
59 			    !entry->padding[2], "padding should be zero");
60 
61 		/*
62 		 * If needed for debug:
63 		 * fprintf(stdout,
64 		 *	"CPUID%lx EAX=0x%lx EBX=0x%lx ECX=0x%lx EDX=0x%lx\n",
65 		 *	entry->function, entry->eax, entry->ebx, entry->ecx,
66 		 *	entry->edx);
67 		 */
68 	}
69 
70 }
71 
72 void test_hv_cpuid_e2big(struct kvm_vm *vm)
73 {
74 	static struct kvm_cpuid2 cpuid = {.nent = 0};
75 	int ret;
76 
77 	ret = _vcpu_ioctl(vm, VCPU_ID, KVM_GET_SUPPORTED_HV_CPUID, &cpuid);
78 
79 	TEST_ASSERT(ret == -1 && errno == E2BIG,
80 		    "KVM_GET_SUPPORTED_HV_CPUID didn't fail with -E2BIG when"
81 		    " it should have: %d %d", ret, errno);
82 }
83 
84 
85 struct kvm_cpuid2 *kvm_get_supported_hv_cpuid(struct kvm_vm *vm)
86 {
87 	int nent = 20; /* should be enough */
88 	static struct kvm_cpuid2 *cpuid;
89 
90 	cpuid = malloc(sizeof(*cpuid) + nent * sizeof(struct kvm_cpuid_entry2));
91 
92 	if (!cpuid) {
93 		perror("malloc");
94 		abort();
95 	}
96 
97 	cpuid->nent = nent;
98 
99 	vcpu_ioctl(vm, VCPU_ID, KVM_GET_SUPPORTED_HV_CPUID, cpuid);
100 
101 	return cpuid;
102 }
103 
104 
105 int main(int argc, char *argv[])
106 {
107 	struct kvm_vm *vm;
108 	int rv;
109 	uint16_t evmcs_ver;
110 	struct kvm_cpuid2 *hv_cpuid_entries;
111 	struct kvm_enable_cap enable_evmcs_cap = {
112 		.cap = KVM_CAP_HYPERV_ENLIGHTENED_VMCS,
113 		 .args[0] = (unsigned long)&evmcs_ver
114 	};
115 
116 	/* Tell stdout not to buffer its content */
117 	setbuf(stdout, NULL);
118 
119 	rv = kvm_check_cap(KVM_CAP_HYPERV_CPUID);
120 	if (!rv) {
121 		fprintf(stderr,
122 			"KVM_CAP_HYPERV_CPUID not supported, skip test\n");
123 		exit(KSFT_SKIP);
124 	}
125 
126 	/* Create VM */
127 	vm = vm_create_default(VCPU_ID, 0, guest_code);
128 
129 	test_hv_cpuid_e2big(vm);
130 
131 	hv_cpuid_entries = kvm_get_supported_hv_cpuid(vm);
132 	if (!hv_cpuid_entries)
133 		return 1;
134 
135 	test_hv_cpuid(hv_cpuid_entries, 0);
136 
137 	free(hv_cpuid_entries);
138 
139 	rv = _vcpu_ioctl(vm, VCPU_ID, KVM_ENABLE_CAP, &enable_evmcs_cap);
140 
141 	if (rv) {
142 		fprintf(stderr,
143 			"Enlightened VMCS is unsupported, skip related test\n");
144 		goto vm_free;
145 	}
146 
147 	hv_cpuid_entries = kvm_get_supported_hv_cpuid(vm);
148 	if (!hv_cpuid_entries)
149 		return 1;
150 
151 	test_hv_cpuid(hv_cpuid_entries, 1);
152 
153 	free(hv_cpuid_entries);
154 
155 vm_free:
156 	kvm_vm_free(vm);
157 
158 	return 0;
159 }
160