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

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * KVM_GET/SET_* tests
   4  *
   5  * Copyright (C) 2018, Red Hat, Inc.
   6  *
   7  * Tests for vCPU state save/restore, including nested guest state.
   8  */
   9 #define _GNU_SOURCE /* for program_invocation_short_name */
  10 #include <fcntl.h>
  11 #include <stdio.h>
  12 #include <stdlib.h>
  13 #include <string.h>
  14 #include <sys/ioctl.h>
  15
  16 #include "test_util.h"
  17
  18 #include "kvm_util.h"
  19 #include "processor.h"
  20 #include "vmx.h"
  21 #include "svm_util.h"
  22
  23 #define L2_GUEST_STACK_SIZE 256
  24
  25 void svm_l2_guest_code(void)
  26 {
  27         GUEST_SYNC(4);
  28         /* Exit to L1 */
  29         vmcall();
  30         GUEST_SYNC(6);
  31         /* Done, exit to L1 and never come back.  */
  32         vmcall();
  33 }
  34
  35 static void svm_l1_guest_code(struct svm_test_data *svm)
  36 {
  37         unsigned long l2_guest_stack[L2_GUEST_STACK_SIZE];
  38         struct vmcb *vmcb = svm->vmcb;
  39
  40         GUEST_ASSERT(svm->vmcb_gpa);
  41         /* Prepare for L2 execution. */
  42         generic_svm_setup(svm, svm_l2_guest_code,
  43                           &l2_guest_stack[L2_GUEST_STACK_SIZE]);
  44
  45         GUEST_SYNC(3);
  46         run_guest(vmcb, svm->vmcb_gpa);
  47         GUEST_ASSERT(vmcb->control.exit_code == SVM_EXIT_VMMCALL);
  48         GUEST_SYNC(5);
  49         vmcb->save.rip += 3;
  50         run_guest(vmcb, svm->vmcb_gpa);
  51         GUEST_ASSERT(vmcb->control.exit_code == SVM_EXIT_VMMCALL);
  52         GUEST_SYNC(7);
  53 }
  54
  55 void vmx_l2_guest_code(void)
  56 {
  57         GUEST_SYNC(6);
  58
  59         /* Exit to L1 */
  60         vmcall();
  61
  62         /* L1 has now set up a shadow VMCS for us.  */
  63         GUEST_ASSERT(vmreadz(GUEST_RIP) == 0xc0ffee);
  64         GUEST_SYNC(10);
  65         GUEST_ASSERT(vmreadz(GUEST_RIP) == 0xc0ffee);
  66         GUEST_ASSERT(!vmwrite(GUEST_RIP, 0xc0fffee));
  67         GUEST_SYNC(11);
  68         GUEST_ASSERT(vmreadz(GUEST_RIP) == 0xc0fffee);
  69         GUEST_ASSERT(!vmwrite(GUEST_RIP, 0xc0ffffee));
  70         GUEST_SYNC(12);
  71
  72         /* Done, exit to L1 and never come back.  */
  73         vmcall();
  74 }
  75
  76 static void vmx_l1_guest_code(struct vmx_pages *vmx_pages)
  77 {
  78         unsigned long l2_guest_stack[L2_GUEST_STACK_SIZE];
  79
  80         GUEST_ASSERT(vmx_pages->vmcs_gpa);
  81         GUEST_ASSERT(prepare_for_vmx_operation(vmx_pages));
  82         GUEST_SYNC(3);
  83         GUEST_ASSERT(load_vmcs(vmx_pages));
  84         GUEST_ASSERT(vmptrstz() == vmx_pages->vmcs_gpa);
  85
  86         GUEST_SYNC(4);
  87         GUEST_ASSERT(vmptrstz() == vmx_pages->vmcs_gpa);
  88
  89         prepare_vmcs(vmx_pages, vmx_l2_guest_code,
  90                      &l2_guest_stack[L2_GUEST_STACK_SIZE]);
  91
  92         GUEST_SYNC(5);
  93         GUEST_ASSERT(vmptrstz() == vmx_pages->vmcs_gpa);
  94         GUEST_ASSERT(!vmlaunch());
  95         GUEST_ASSERT(vmptrstz() == vmx_pages->vmcs_gpa);
  96         GUEST_ASSERT(vmreadz(VM_EXIT_REASON) == EXIT_REASON_VMCALL);
  97
  98         /* Check that the launched state is preserved.  */
  99         GUEST_ASSERT(vmlaunch());
 100
 101         GUEST_ASSERT(!vmresume());
 102         GUEST_ASSERT(vmreadz(VM_EXIT_REASON) == EXIT_REASON_VMCALL);
 103
 104         GUEST_SYNC(7);
 105         GUEST_ASSERT(vmreadz(VM_EXIT_REASON) == EXIT_REASON_VMCALL);
 106
 107         GUEST_ASSERT(!vmresume());
 108         GUEST_ASSERT(vmreadz(VM_EXIT_REASON) == EXIT_REASON_VMCALL);
 109
 110         vmwrite(GUEST_RIP, vmreadz(GUEST_RIP) + 3);
 111
 112         vmwrite(SECONDARY_VM_EXEC_CONTROL, SECONDARY_EXEC_SHADOW_VMCS);
 113         vmwrite(VMCS_LINK_POINTER, vmx_pages->shadow_vmcs_gpa);
 114
 115         GUEST_ASSERT(!vmptrld(vmx_pages->shadow_vmcs_gpa));
 116         GUEST_ASSERT(vmlaunch());
 117         GUEST_SYNC(8);
 118         GUEST_ASSERT(vmlaunch());
 119         GUEST_ASSERT(vmresume());
 120
 121         vmwrite(GUEST_RIP, 0xc0ffee);
 122         GUEST_SYNC(9);
 123         GUEST_ASSERT(vmreadz(GUEST_RIP) == 0xc0ffee);
 124
 125         GUEST_ASSERT(!vmptrld(vmx_pages->vmcs_gpa));
 126         GUEST_ASSERT(!vmresume());
 127         GUEST_ASSERT(vmreadz(VM_EXIT_REASON) == EXIT_REASON_VMCALL);
 128
 129         GUEST_ASSERT(!vmptrld(vmx_pages->shadow_vmcs_gpa));
 130         GUEST_ASSERT(vmreadz(GUEST_RIP) == 0xc0ffffee);
 131         GUEST_ASSERT(vmlaunch());
 132         GUEST_ASSERT(vmresume());
 133         GUEST_SYNC(13);
 134         GUEST_ASSERT(vmreadz(GUEST_RIP) == 0xc0ffffee);
 135         GUEST_ASSERT(vmlaunch());
 136         GUEST_ASSERT(vmresume());
 137 }
 138
 139 static void __attribute__((__flatten__)) guest_code(void *arg)
 140 {
 141         GUEST_SYNC(1);
 142         GUEST_SYNC(2);
 143
 144         if (arg) {
 145                 if (this_cpu_has(X86_FEATURE_SVM))
 146                         svm_l1_guest_code(arg);
 147                 else
 148                         vmx_l1_guest_code(arg);
 149         }
 150
 151         GUEST_DONE();
 152 }
 153
 154 int main(int argc, char *argv[])
 155 {
 156         vm_vaddr_t nested_gva = 0;
 157
 158         struct kvm_regs regs1, regs2;
 159         struct kvm_vcpu *vcpu;
 160         struct kvm_vm *vm;
 161         struct kvm_x86_state *state;
 162         struct ucall uc;
 163         int stage;
 164
 165         /* Create VM */
 166         vm = vm_create_with_one_vcpu(&vcpu, guest_code);
 167
 168         vcpu_regs_get(vcpu, &regs1);
 169
 170         if (kvm_has_cap(KVM_CAP_NESTED_STATE)) {
 171                 if (kvm_cpu_has(X86_FEATURE_SVM))
 172                         vcpu_alloc_svm(vm, &nested_gva);
 173                 else if (kvm_cpu_has(X86_FEATURE_VMX))
 174                         vcpu_alloc_vmx(vm, &nested_gva);
 175         }
 176
 177         if (!nested_gva)
 178                 pr_info("will skip nested state checks\n");
 179
 180         vcpu_args_set(vcpu, 1, nested_gva);
 181
 182         for (stage = 1;; stage++) {
 183                 vcpu_run(vcpu);
 184                 TEST_ASSERT_KVM_EXIT_REASON(vcpu, KVM_EXIT_IO);
 185
 186                 switch (get_ucall(vcpu, &uc)) {
 187                 case UCALL_ABORT:
 188                         REPORT_GUEST_ASSERT(uc);
 189                         /* NOT REACHED */
 190                 case UCALL_SYNC:
 191                         break;
 192                 case UCALL_DONE:
 193                         goto done;
 194                 default:
 195                         TEST_FAIL("Unknown ucall %lu", uc.cmd);
 196                 }
 197
 198                 /* UCALL_SYNC is handled here.  */
 199                 TEST_ASSERT(!strcmp((const char *)uc.args[0], "hello") &&
 200                             uc.args[1] == stage, "Stage %d: Unexpected register values vmexit, got %lx",
 201                             stage, (ulong)uc.args[1]);
 202
 203                 state = vcpu_save_state(vcpu);
 204                 memset(&regs1, 0, sizeof(regs1));
 205                 vcpu_regs_get(vcpu, &regs1);
 206
 207                 kvm_vm_release(vm);
 208
 209                 /* Restore state in a new VM.  */
 210                 vcpu = vm_recreate_with_one_vcpu(vm);
 211                 vcpu_load_state(vcpu, state);
 212                 kvm_x86_state_cleanup(state);
 213
 214                 memset(&regs2, 0, sizeof(regs2));
 215                 vcpu_regs_get(vcpu, &regs2);
 216                 TEST_ASSERT(!memcmp(&regs1, &regs2, sizeof(regs2)),
 217                             "Unexpected register values after vcpu_load_state; rdi: %lx rsi: %lx",
 218                             (ulong) regs2.rdi, (ulong) regs2.rsi);
 219         }
 220
 221 done:
 222         kvm_vm_free(vm);
 223 }