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 #include "vmx.h"
22
23 #define VCPU_ID 0
24
guest_code(void)25 static void guest_code(void)
26 {
27 }
28
smt_possible(void)29 static int smt_possible(void)
30 {
31 char buf[16];
32 FILE *f;
33 bool res = 1;
34
35 f = fopen("/sys/devices/system/cpu/smt/control", "r");
36 if (f) {
37 if (fread(buf, sizeof(*buf), sizeof(buf), f) > 0) {
38 if (!strncmp(buf, "forceoff", 8) ||
39 !strncmp(buf, "notsupported", 12))
40 res = 0;
41 }
42 fclose(f);
43 }
44
45 return res;
46 }
47
test_hv_cpuid(struct kvm_cpuid2 * hv_cpuid_entries,int evmcs_enabled)48 static void test_hv_cpuid(struct kvm_cpuid2 *hv_cpuid_entries,
49 int evmcs_enabled)
50 {
51 int i;
52
53 if (!evmcs_enabled)
54 TEST_ASSERT(hv_cpuid_entries->nent == 6,
55 "KVM_GET_SUPPORTED_HV_CPUID should return 6 entries"
56 " when Enlightened VMCS is disabled (returned %d)",
57 hv_cpuid_entries->nent);
58 else
59 TEST_ASSERT(hv_cpuid_entries->nent == 7,
60 "KVM_GET_SUPPORTED_HV_CPUID should return 7 entries"
61 " when Enlightened VMCS is enabled (returned %d)",
62 hv_cpuid_entries->nent);
63
64 for (i = 0; i < hv_cpuid_entries->nent; i++) {
65 struct kvm_cpuid_entry2 *entry = &hv_cpuid_entries->entries[i];
66
67 TEST_ASSERT((entry->function >= 0x40000000) &&
68 (entry->function <= 0x4000000A),
69 "function %lx is our of supported range",
70 entry->function);
71
72 TEST_ASSERT(entry->index == 0,
73 ".index field should be zero");
74
75 TEST_ASSERT(entry->flags == 0,
76 ".flags field should be zero");
77
78 TEST_ASSERT(!entry->padding[0] && !entry->padding[1] &&
79 !entry->padding[2], "padding should be zero");
80
81 if (entry->function == 0x40000004) {
82 int nononarchcs = !!(entry->eax & (1UL << 18));
83
84 TEST_ASSERT(nononarchcs == !smt_possible(),
85 "NoNonArchitecturalCoreSharing bit"
86 " doesn't reflect SMT setting");
87 }
88
89 /*
90 * If needed for debug:
91 * fprintf(stdout,
92 * "CPUID%lx EAX=0x%lx EBX=0x%lx ECX=0x%lx EDX=0x%lx\n",
93 * entry->function, entry->eax, entry->ebx, entry->ecx,
94 * entry->edx);
95 */
96 }
97
98 }
99
test_hv_cpuid_e2big(struct kvm_vm * vm)100 void test_hv_cpuid_e2big(struct kvm_vm *vm)
101 {
102 static struct kvm_cpuid2 cpuid = {.nent = 0};
103 int ret;
104
105 ret = _vcpu_ioctl(vm, VCPU_ID, KVM_GET_SUPPORTED_HV_CPUID, &cpuid);
106
107 TEST_ASSERT(ret == -1 && errno == E2BIG,
108 "KVM_GET_SUPPORTED_HV_CPUID didn't fail with -E2BIG when"
109 " it should have: %d %d", ret, errno);
110 }
111
112
kvm_get_supported_hv_cpuid(struct kvm_vm * vm)113 struct kvm_cpuid2 *kvm_get_supported_hv_cpuid(struct kvm_vm *vm)
114 {
115 int nent = 20; /* should be enough */
116 static struct kvm_cpuid2 *cpuid;
117
118 cpuid = malloc(sizeof(*cpuid) + nent * sizeof(struct kvm_cpuid_entry2));
119
120 if (!cpuid) {
121 perror("malloc");
122 abort();
123 }
124
125 cpuid->nent = nent;
126
127 vcpu_ioctl(vm, VCPU_ID, KVM_GET_SUPPORTED_HV_CPUID, cpuid);
128
129 return cpuid;
130 }
131
132
main(int argc,char * argv[])133 int main(int argc, char *argv[])
134 {
135 struct kvm_vm *vm;
136 int rv;
137 struct kvm_cpuid2 *hv_cpuid_entries;
138
139 /* Tell stdout not to buffer its content */
140 setbuf(stdout, NULL);
141
142 rv = kvm_check_cap(KVM_CAP_HYPERV_CPUID);
143 if (!rv) {
144 fprintf(stderr,
145 "KVM_CAP_HYPERV_CPUID not supported, skip test\n");
146 exit(KSFT_SKIP);
147 }
148
149 /* Create VM */
150 vm = vm_create_default(VCPU_ID, 0, guest_code);
151
152 test_hv_cpuid_e2big(vm);
153
154 hv_cpuid_entries = kvm_get_supported_hv_cpuid(vm);
155 if (!hv_cpuid_entries)
156 return 1;
157
158 test_hv_cpuid(hv_cpuid_entries, 0);
159
160 free(hv_cpuid_entries);
161
162 if (!kvm_check_cap(KVM_CAP_HYPERV_ENLIGHTENED_VMCS)) {
163 fprintf(stderr,
164 "Enlightened VMCS is unsupported, skip related test\n");
165 goto vm_free;
166 }
167
168 vcpu_enable_evmcs(vm, VCPU_ID);
169
170 hv_cpuid_entries = kvm_get_supported_hv_cpuid(vm);
171 if (!hv_cpuid_entries)
172 return 1;
173
174 test_hv_cpuid(hv_cpuid_entries, 1);
175
176 free(hv_cpuid_entries);
177
178 vm_free:
179 kvm_vm_free(vm);
180
181 return 0;
182 }
183