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 bool smt_possible(void)
30 {
31 char buf[16];
32 FILE *f;
33 bool res = true;
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 = false;
41 }
42 fclose(f);
43 }
44
45 return res;
46 }
47
test_hv_cpuid(struct kvm_cpuid2 * hv_cpuid_entries,bool evmcs_enabled)48 static void test_hv_cpuid(struct kvm_cpuid2 *hv_cpuid_entries,
49 bool evmcs_enabled)
50 {
51 int i;
52 int nent = 9;
53 u32 test_val;
54
55 if (evmcs_enabled)
56 nent += 1; /* 0x4000000A */
57
58 TEST_ASSERT(hv_cpuid_entries->nent == nent,
59 "KVM_GET_SUPPORTED_HV_CPUID should return %d entries"
60 " with evmcs=%d (returned %d)",
61 nent, evmcs_enabled, hv_cpuid_entries->nent);
62
63 for (i = 0; i < hv_cpuid_entries->nent; i++) {
64 struct kvm_cpuid_entry2 *entry = &hv_cpuid_entries->entries[i];
65
66 TEST_ASSERT((entry->function >= 0x40000000) &&
67 (entry->function <= 0x40000082),
68 "function %x is our of supported range",
69 entry->function);
70
71 TEST_ASSERT(evmcs_enabled || (entry->function != 0x4000000A),
72 "0x4000000A leaf should not be reported");
73
74 TEST_ASSERT(entry->index == 0,
75 ".index field should be zero");
76
77 TEST_ASSERT(entry->flags == 0,
78 ".flags field should be zero");
79
80 TEST_ASSERT(!entry->padding[0] && !entry->padding[1] &&
81 !entry->padding[2], "padding should be zero");
82
83 switch (entry->function) {
84 case 0x40000000:
85 test_val = 0x40000082;
86
87 TEST_ASSERT(entry->eax == test_val,
88 "Wrong max leaf report in 0x40000000.EAX: %x"
89 " (evmcs=%d)",
90 entry->eax, evmcs_enabled
91 );
92 break;
93 case 0x40000004:
94 test_val = entry->eax & (1UL << 18);
95
96 TEST_ASSERT(!!test_val == !smt_possible(),
97 "NoNonArchitecturalCoreSharing bit"
98 " doesn't reflect SMT setting");
99 break;
100 }
101
102 /*
103 * If needed for debug:
104 * fprintf(stdout,
105 * "CPUID%lx EAX=0x%lx EBX=0x%lx ECX=0x%lx EDX=0x%lx\n",
106 * entry->function, entry->eax, entry->ebx, entry->ecx,
107 * entry->edx);
108 */
109 }
110
111 }
112
test_hv_cpuid_e2big(struct kvm_vm * vm)113 void test_hv_cpuid_e2big(struct kvm_vm *vm)
114 {
115 static struct kvm_cpuid2 cpuid = {.nent = 0};
116 int ret;
117
118 ret = _vcpu_ioctl(vm, VCPU_ID, KVM_GET_SUPPORTED_HV_CPUID, &cpuid);
119
120 TEST_ASSERT(ret == -1 && errno == E2BIG,
121 "KVM_GET_SUPPORTED_HV_CPUID didn't fail with -E2BIG when"
122 " it should have: %d %d", ret, errno);
123 }
124
125
kvm_get_supported_hv_cpuid(struct kvm_vm * vm)126 struct kvm_cpuid2 *kvm_get_supported_hv_cpuid(struct kvm_vm *vm)
127 {
128 int nent = 20; /* should be enough */
129 static struct kvm_cpuid2 *cpuid;
130
131 cpuid = malloc(sizeof(*cpuid) + nent * sizeof(struct kvm_cpuid_entry2));
132
133 if (!cpuid) {
134 perror("malloc");
135 abort();
136 }
137
138 cpuid->nent = nent;
139
140 vcpu_ioctl(vm, VCPU_ID, KVM_GET_SUPPORTED_HV_CPUID, cpuid);
141
142 return cpuid;
143 }
144
145
main(int argc,char * argv[])146 int main(int argc, char *argv[])
147 {
148 struct kvm_vm *vm;
149 int rv, stage;
150 struct kvm_cpuid2 *hv_cpuid_entries;
151 bool evmcs_enabled;
152
153 /* Tell stdout not to buffer its content */
154 setbuf(stdout, NULL);
155
156 rv = kvm_check_cap(KVM_CAP_HYPERV_CPUID);
157 if (!rv) {
158 print_skip("KVM_CAP_HYPERV_CPUID not supported");
159 exit(KSFT_SKIP);
160 }
161
162 for (stage = 0; stage < 3; stage++) {
163 evmcs_enabled = false;
164
165 vm = vm_create_default(VCPU_ID, 0, guest_code);
166 switch (stage) {
167 case 0:
168 test_hv_cpuid_e2big(vm);
169 continue;
170 case 1:
171 break;
172 case 2:
173 if (!nested_vmx_supported() ||
174 !kvm_check_cap(KVM_CAP_HYPERV_ENLIGHTENED_VMCS)) {
175 print_skip("Enlightened VMCS is unsupported");
176 continue;
177 }
178 vcpu_enable_evmcs(vm, VCPU_ID);
179 evmcs_enabled = true;
180 break;
181 }
182
183 hv_cpuid_entries = kvm_get_supported_hv_cpuid(vm);
184 test_hv_cpuid(hv_cpuid_entries, evmcs_enabled);
185 free(hv_cpuid_entries);
186 kvm_vm_free(vm);
187 }
188
189 return 0;
190 }
191