root/tools/testing/selftests/kvm/x86_64/vmx_set_nested_state_test.c

DEFINITIONS

1. test_nested_state
2. test_nested_state_expect_errno
3. test_nested_state_expect_einval
4. test_nested_state_expect_efault
5. set_revision_id_for_vmcs12
6. set_default_state
7. set_default_vmx_state
8. test_vmx_nested_state
9. main

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * vmx_set_nested_state_test
   4  *
   5  * Copyright (C) 2019, Google LLC.
   6  *
   7  * This test verifies the integrity of calling the ioctl KVM_SET_NESTED_STATE.
   8  */
   9 
  10 #include "test_util.h"
  11 #include "kvm_util.h"
  12 #include "processor.h"
  13 #include "vmx.h"
  14 
  15 #include <errno.h>
  16 #include <linux/kvm.h>
  17 #include <string.h>
  18 #include <sys/ioctl.h>
  19 #include <unistd.h>
  20 
  21 /*
  22  * Mirror of VMCS12_REVISION in arch/x86/kvm/vmx/vmcs12.h. If that value
  23  * changes this should be updated.
  24  */
  25 #define VMCS12_REVISION 0x11e57ed0
  26 #define VCPU_ID 5
  27 
  28 bool have_evmcs;
  29 
  30 void test_nested_state(struct kvm_vm *vm, struct kvm_nested_state *state)
  31 {
  32         vcpu_nested_state_set(vm, VCPU_ID, state, false);
  33 }
  34 
  35 void test_nested_state_expect_errno(struct kvm_vm *vm,
  36                                     struct kvm_nested_state *state,
  37                                     int expected_errno)
  38 {
  39         int rv;
  40 
  41         rv = vcpu_nested_state_set(vm, VCPU_ID, state, true);
  42         TEST_ASSERT(rv == -1 && errno == expected_errno,
  43                 "Expected %s (%d) from vcpu_nested_state_set but got rv: %i errno: %s (%d)",
  44                 strerror(expected_errno), expected_errno, rv, strerror(errno),
  45                 errno);
  46 }
  47 
  48 void test_nested_state_expect_einval(struct kvm_vm *vm,
  49                                      struct kvm_nested_state *state)
  50 {
  51         test_nested_state_expect_errno(vm, state, EINVAL);
  52 }
  53 
  54 void test_nested_state_expect_efault(struct kvm_vm *vm,
  55                                      struct kvm_nested_state *state)
  56 {
  57         test_nested_state_expect_errno(vm, state, EFAULT);
  58 }
  59 
  60 void set_revision_id_for_vmcs12(struct kvm_nested_state *state,
  61                                 u32 vmcs12_revision)
  62 {
  63         /* Set revision_id in vmcs12 to vmcs12_revision. */
  64         memcpy(&state->data, &vmcs12_revision, sizeof(u32));
  65 }
  66 
  67 void set_default_state(struct kvm_nested_state *state)
  68 {
  69         memset(state, 0, sizeof(*state));
  70         state->flags = KVM_STATE_NESTED_RUN_PENDING |
  71                        KVM_STATE_NESTED_GUEST_MODE;
  72         state->format = 0;
  73         state->size = sizeof(*state);
  74 }
  75 
  76 void set_default_vmx_state(struct kvm_nested_state *state, int size)
  77 {
  78         memset(state, 0, size);
  79         state->flags = KVM_STATE_NESTED_GUEST_MODE  |
  80                         KVM_STATE_NESTED_RUN_PENDING;
  81         if (have_evmcs)
  82                 state->flags |= KVM_STATE_NESTED_EVMCS;
  83         state->format = 0;
  84         state->size = size;
  85         state->hdr.vmx.vmxon_pa = 0x1000;
  86         state->hdr.vmx.vmcs12_pa = 0x2000;
  87         state->hdr.vmx.smm.flags = 0;
  88         set_revision_id_for_vmcs12(state, VMCS12_REVISION);
  89 }
  90 
  91 void test_vmx_nested_state(struct kvm_vm *vm)
  92 {
  93         /* Add a page for VMCS12. */
  94         const int state_sz = sizeof(struct kvm_nested_state) + getpagesize();
  95         struct kvm_nested_state *state =
  96                 (struct kvm_nested_state *)malloc(state_sz);
  97 
  98         /* The format must be set to 0. 0 for VMX, 1 for SVM. */
  99         set_default_vmx_state(state, state_sz);
 100         state->format = 1;
 101         test_nested_state_expect_einval(vm, state);
 102 
 103         /*
 104          * We cannot virtualize anything if the guest does not have VMX
 105          * enabled.
 106          */
 107         set_default_vmx_state(state, state_sz);
 108         test_nested_state_expect_einval(vm, state);
 109 
 110         /*
 111          * We cannot virtualize anything if the guest does not have VMX
 112          * enabled.  We expect KVM_SET_NESTED_STATE to return 0 if vmxon_pa
 113          * is set to -1ull, but the flags must be zero.
 114          */
 115         set_default_vmx_state(state, state_sz);
 116         state->hdr.vmx.vmxon_pa = -1ull;
 117         test_nested_state_expect_einval(vm, state);
 118 
 119         state->hdr.vmx.vmcs12_pa = -1ull;
 120         state->flags = KVM_STATE_NESTED_EVMCS;
 121         test_nested_state_expect_einval(vm, state);
 122 
 123         state->flags = 0;
 124         test_nested_state(vm, state);
 125 
 126         /* Enable VMX in the guest CPUID. */
 127         vcpu_set_cpuid(vm, VCPU_ID, kvm_get_supported_cpuid());
 128 
 129         /*
 130          * Setting vmxon_pa == -1ull and vmcs_pa == -1ull exits early without
 131          * setting the nested state but flags other than eVMCS must be clear.
 132          * The eVMCS flag can be set if the enlightened VMCS capability has
 133          * been enabled.
 134          */
 135         set_default_vmx_state(state, state_sz);
 136         state->hdr.vmx.vmxon_pa = -1ull;
 137         state->hdr.vmx.vmcs12_pa = -1ull;
 138         test_nested_state_expect_einval(vm, state);
 139 
 140         state->flags &= KVM_STATE_NESTED_EVMCS;
 141         if (have_evmcs) {
 142                 test_nested_state_expect_einval(vm, state);
 143                 vcpu_enable_evmcs(vm, VCPU_ID);
 144         }
 145         test_nested_state(vm, state);
 146 
 147         /* It is invalid to have vmxon_pa == -1ull and SMM flags non-zero. */
 148         state->hdr.vmx.smm.flags = 1;
 149         test_nested_state_expect_einval(vm, state);
 150 
 151         /* It is invalid to have vmxon_pa == -1ull and vmcs_pa != -1ull. */
 152         set_default_vmx_state(state, state_sz);
 153         state->hdr.vmx.vmxon_pa = -1ull;
 154         state->flags = 0;
 155         test_nested_state_expect_einval(vm, state);
 156 
 157         /* It is invalid to have vmxon_pa set to a non-page aligned address. */
 158         set_default_vmx_state(state, state_sz);
 159         state->hdr.vmx.vmxon_pa = 1;
 160         test_nested_state_expect_einval(vm, state);
 161 
 162         /*
 163          * It is invalid to have KVM_STATE_NESTED_SMM_GUEST_MODE and
 164          * KVM_STATE_NESTED_GUEST_MODE set together.
 165          */
 166         set_default_vmx_state(state, state_sz);
 167         state->flags = KVM_STATE_NESTED_GUEST_MODE  |
 168                       KVM_STATE_NESTED_RUN_PENDING;
 169         state->hdr.vmx.smm.flags = KVM_STATE_NESTED_SMM_GUEST_MODE;
 170         test_nested_state_expect_einval(vm, state);
 171 
 172         /*
 173          * It is invalid to have any of the SMM flags set besides:
 174          *      KVM_STATE_NESTED_SMM_GUEST_MODE
 175          *      KVM_STATE_NESTED_SMM_VMXON
 176          */
 177         set_default_vmx_state(state, state_sz);
 178         state->hdr.vmx.smm.flags = ~(KVM_STATE_NESTED_SMM_GUEST_MODE |
 179                                 KVM_STATE_NESTED_SMM_VMXON);
 180         test_nested_state_expect_einval(vm, state);
 181 
 182         /* Outside SMM, SMM flags must be zero. */
 183         set_default_vmx_state(state, state_sz);
 184         state->flags = 0;
 185         state->hdr.vmx.smm.flags = KVM_STATE_NESTED_SMM_GUEST_MODE;
 186         test_nested_state_expect_einval(vm, state);
 187 
 188         /* Size must be large enough to fit kvm_nested_state and vmcs12. */
 189         set_default_vmx_state(state, state_sz);
 190         state->size = sizeof(*state);
 191         test_nested_state(vm, state);
 192 
 193         /* vmxon_pa cannot be the same address as vmcs_pa. */
 194         set_default_vmx_state(state, state_sz);
 195         state->hdr.vmx.vmxon_pa = 0;
 196         state->hdr.vmx.vmcs12_pa = 0;
 197         test_nested_state_expect_einval(vm, state);
 198 
 199         /* The revision id for vmcs12 must be VMCS12_REVISION. */
 200         set_default_vmx_state(state, state_sz);
 201         set_revision_id_for_vmcs12(state, 0);
 202         test_nested_state_expect_einval(vm, state);
 203 
 204         /*
 205          * Test that if we leave nesting the state reflects that when we get
 206          * it again.
 207          */
 208         set_default_vmx_state(state, state_sz);
 209         state->hdr.vmx.vmxon_pa = -1ull;
 210         state->hdr.vmx.vmcs12_pa = -1ull;
 211         state->flags = 0;
 212         test_nested_state(vm, state);
 213         vcpu_nested_state_get(vm, VCPU_ID, state);
 214         TEST_ASSERT(state->size >= sizeof(*state) && state->size <= state_sz,
 215                     "Size must be between %d and %d.  The size returned was %d.",
 216                     sizeof(*state), state_sz, state->size);
 217         TEST_ASSERT(state->hdr.vmx.vmxon_pa == -1ull, "vmxon_pa must be -1ull.");
 218         TEST_ASSERT(state->hdr.vmx.vmcs12_pa == -1ull, "vmcs_pa must be -1ull.");
 219 
 220         free(state);
 221 }
 222 
 223 int main(int argc, char *argv[])
 224 {
 225         struct kvm_vm *vm;
 226         struct kvm_nested_state state;
 227 
 228         have_evmcs = kvm_check_cap(KVM_CAP_HYPERV_ENLIGHTENED_VMCS);
 229 
 230         if (!kvm_check_cap(KVM_CAP_NESTED_STATE)) {
 231                 printf("KVM_CAP_NESTED_STATE not available, skipping test\n");
 232                 exit(KSFT_SKIP);
 233         }
 234 
 235         /*
 236          * AMD currently does not implement set_nested_state, so for now we
 237          * just early out.
 238          */
 239         nested_vmx_check_supported();
 240 
 241         vm = vm_create_default(VCPU_ID, 0, 0);
 242 
 243         /* Passing a NULL kvm_nested_state causes a EFAULT. */
 244         test_nested_state_expect_efault(vm, NULL);
 245 
 246         /* 'size' cannot be smaller than sizeof(kvm_nested_state). */
 247         set_default_state(&state);
 248         state.size = 0;
 249         test_nested_state_expect_einval(vm, &state);
 250 
 251         /*
 252          * Setting the flags 0xf fails the flags check.  The only flags that
 253          * can be used are:
 254          *     KVM_STATE_NESTED_GUEST_MODE
 255          *     KVM_STATE_NESTED_RUN_PENDING
 256          *     KVM_STATE_NESTED_EVMCS
 257          */
 258         set_default_state(&state);
 259         state.flags = 0xf;
 260         test_nested_state_expect_einval(vm, &state);
 261 
 262         /*
 263          * If KVM_STATE_NESTED_RUN_PENDING is set then
 264          * KVM_STATE_NESTED_GUEST_MODE has to be set as well.
 265          */
 266         set_default_state(&state);
 267         state.flags = KVM_STATE_NESTED_RUN_PENDING;
 268         test_nested_state_expect_einval(vm, &state);
 269 
 270         test_vmx_nested_state(vm);
 271 
 272         kvm_vm_free(vm);
 273         return 0;
 274 }