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

   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->index == 0,
  56                             ".index field should be zero");
  57
  58                 TEST_ASSERT(entry->flags == 0,
  59                             ".flags field should be zero");
  60
  61                 TEST_ASSERT(!entry->padding[0] && !entry->padding[1] &&
  62                             !entry->padding[2], "padding should be zero");
  63
  64                 /*
  65                  * If needed for debug:
  66                  * fprintf(stdout,
  67                  *      "CPUID%lx EAX=0x%lx EBX=0x%lx ECX=0x%lx EDX=0x%lx\n",
  68                  *      entry->function, entry->eax, entry->ebx, entry->ecx,
  69                  *      entry->edx);
  70                  */
  71         }
  72
  73 }
  74
  75 void test_hv_cpuid_e2big(struct kvm_vm *vm)
  76 {
  77         static struct kvm_cpuid2 cpuid = {.nent = 0};
  78         int ret;
  79
  80         ret = _vcpu_ioctl(vm, VCPU_ID, KVM_GET_SUPPORTED_HV_CPUID, &cpuid);
  81
  82         TEST_ASSERT(ret == -1 && errno == E2BIG,
  83                     "KVM_GET_SUPPORTED_HV_CPUID didn't fail with -E2BIG when"
  84                     " it should have: %d %d", ret, errno);
  85 }
  86
  87
  88 struct kvm_cpuid2 *kvm_get_supported_hv_cpuid(struct kvm_vm *vm)
  89 {
  90         int nent = 20; /* should be enough */
  91         static struct kvm_cpuid2 *cpuid;
  92         int ret;
  93
  94         cpuid = malloc(sizeof(*cpuid) + nent * sizeof(struct kvm_cpuid_entry2));
  95
  96         if (!cpuid) {
  97                 perror("malloc");
  98                 abort();
  99         }
 100
 101         cpuid->nent = nent;
 102
 103         vcpu_ioctl(vm, VCPU_ID, KVM_GET_SUPPORTED_HV_CPUID, cpuid);
 104
 105         return cpuid;
 106 }
 107
 108
 109 int main(int argc, char *argv[])
 110 {
 111         struct kvm_vm *vm;
 112         int rv;
 113         uint16_t evmcs_ver;
 114         struct kvm_cpuid2 *hv_cpuid_entries;
 115         struct kvm_enable_cap enable_evmcs_cap = {
 116                 .cap = KVM_CAP_HYPERV_ENLIGHTENED_VMCS,
 117                  .args[0] = (unsigned long)&evmcs_ver
 118         };
 119
 120         /* Tell stdout not to buffer its content */
 121         setbuf(stdout, NULL);
 122
 123         rv = kvm_check_cap(KVM_CAP_HYPERV_CPUID);
 124         if (!rv) {
 125                 fprintf(stderr,
 126                         "KVM_CAP_HYPERV_CPUID not supported, skip test\n");
 127                 exit(KSFT_SKIP);
 128         }
 129
 130         /* Create VM */
 131         vm = vm_create_default(VCPU_ID, 0, guest_code);
 132
 133         test_hv_cpuid_e2big(vm);
 134
 135         hv_cpuid_entries = kvm_get_supported_hv_cpuid(vm);
 136         if (!hv_cpuid_entries)
 137                 return 1;
 138
 139         test_hv_cpuid(hv_cpuid_entries, 0);
 140
 141         free(hv_cpuid_entries);
 142
 143         rv = _vcpu_ioctl(vm, VCPU_ID, KVM_ENABLE_CAP, &enable_evmcs_cap);
 144
 145         if (rv) {
 146                 fprintf(stderr,
 147                         "Enlightened VMCS is unsupported, skip related test\n");
 148                 goto vm_free;
 149         }
 150
 151         hv_cpuid_entries = kvm_get_supported_hv_cpuid(vm);
 152         if (!hv_cpuid_entries)
 153                 return 1;
 154
 155         test_hv_cpuid(hv_cpuid_entries, 1);
 156
 157         free(hv_cpuid_entries);
 158
 159 vm_free:
 160         kvm_vm_free(vm);
 161
 162         return 0;
 163 }