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

   1 /*
   2  * KVM_GET/SET_* tests
   3  *
   4  * Copyright (C) 2018, Red Hat, Inc.
   5  *
   6  * This work is licensed under the terms of the GNU GPL, version 2.
   7  *
   8  * Tests for vCPU state save/restore, including nested guest state.
   9  */
  10 #define _GNU_SOURCE /* for program_invocation_short_name */
  11 #include <fcntl.h>
  12 #include <stdio.h>
  13 #include <stdlib.h>
  14 #include <string.h>
  15 #include <sys/ioctl.h>
  16
  17 #include "test_util.h"
  18
  19 #include "kvm_util.h"
  20 #include "processor.h"
  21 #include "vmx.h"
  22
  23 #define VCPU_ID         5
  24
  25 static bool have_nested_state;
  26
  27 void l2_guest_code(void)
  28 {
  29         GUEST_SYNC(6);
  30
  31         /* Exit to L1 */
  32         vmcall();
  33
  34         /* L1 has now set up a shadow VMCS for us.  */
  35         GUEST_ASSERT(vmreadz(GUEST_RIP) == 0xc0ffee);
  36         GUEST_SYNC(10);
  37         GUEST_ASSERT(vmreadz(GUEST_RIP) == 0xc0ffee);
  38         GUEST_ASSERT(!vmwrite(GUEST_RIP, 0xc0fffee));
  39         GUEST_SYNC(11);
  40         GUEST_ASSERT(vmreadz(GUEST_RIP) == 0xc0fffee);
  41         GUEST_ASSERT(!vmwrite(GUEST_RIP, 0xc0ffffee));
  42         GUEST_SYNC(12);
  43
  44         /* Done, exit to L1 and never come back.  */
  45         vmcall();
  46 }
  47
  48 void l1_guest_code(struct vmx_pages *vmx_pages)
  49 {
  50 #define L2_GUEST_STACK_SIZE 64
  51         unsigned long l2_guest_stack[L2_GUEST_STACK_SIZE];
  52
  53         GUEST_ASSERT(vmx_pages->vmcs_gpa);
  54         GUEST_ASSERT(prepare_for_vmx_operation(vmx_pages));
  55         GUEST_SYNC(3);
  56         GUEST_ASSERT(load_vmcs(vmx_pages));
  57         GUEST_ASSERT(vmptrstz() == vmx_pages->vmcs_gpa);
  58
  59         GUEST_SYNC(4);
  60         GUEST_ASSERT(vmptrstz() == vmx_pages->vmcs_gpa);
  61
  62         prepare_vmcs(vmx_pages, l2_guest_code,
  63                      &l2_guest_stack[L2_GUEST_STACK_SIZE]);
  64
  65         GUEST_SYNC(5);
  66         GUEST_ASSERT(vmptrstz() == vmx_pages->vmcs_gpa);
  67         GUEST_ASSERT(!vmlaunch());
  68         GUEST_ASSERT(vmptrstz() == vmx_pages->vmcs_gpa);
  69         GUEST_ASSERT(vmreadz(VM_EXIT_REASON) == EXIT_REASON_VMCALL);
  70
  71         /* Check that the launched state is preserved.  */
  72         GUEST_ASSERT(vmlaunch());
  73
  74         GUEST_ASSERT(!vmresume());
  75         GUEST_ASSERT(vmreadz(VM_EXIT_REASON) == EXIT_REASON_VMCALL);
  76
  77         GUEST_SYNC(7);
  78         GUEST_ASSERT(vmreadz(VM_EXIT_REASON) == EXIT_REASON_VMCALL);
  79
  80         GUEST_ASSERT(!vmresume());
  81         GUEST_ASSERT(vmreadz(VM_EXIT_REASON) == EXIT_REASON_VMCALL);
  82
  83         vmwrite(GUEST_RIP, vmreadz(GUEST_RIP) + 3);
  84
  85         vmwrite(SECONDARY_VM_EXEC_CONTROL, SECONDARY_EXEC_SHADOW_VMCS);
  86         vmwrite(VMCS_LINK_POINTER, vmx_pages->shadow_vmcs_gpa);
  87
  88         GUEST_ASSERT(!vmptrld(vmx_pages->shadow_vmcs_gpa));
  89         GUEST_ASSERT(vmlaunch());
  90         GUEST_SYNC(8);
  91         GUEST_ASSERT(vmlaunch());
  92         GUEST_ASSERT(vmresume());
  93
  94         vmwrite(GUEST_RIP, 0xc0ffee);
  95         GUEST_SYNC(9);
  96         GUEST_ASSERT(vmreadz(GUEST_RIP) == 0xc0ffee);
  97
  98         GUEST_ASSERT(!vmptrld(vmx_pages->vmcs_gpa));
  99         GUEST_ASSERT(!vmresume());
 100         GUEST_ASSERT(vmreadz(VM_EXIT_REASON) == EXIT_REASON_VMCALL);
 101
 102         GUEST_ASSERT(!vmptrld(vmx_pages->shadow_vmcs_gpa));
 103         GUEST_ASSERT(vmreadz(GUEST_RIP) == 0xc0ffffee);
 104         GUEST_ASSERT(vmlaunch());
 105         GUEST_ASSERT(vmresume());
 106         GUEST_SYNC(13);
 107         GUEST_ASSERT(vmreadz(GUEST_RIP) == 0xc0ffffee);
 108         GUEST_ASSERT(vmlaunch());
 109         GUEST_ASSERT(vmresume());
 110 }
 111
 112 void guest_code(struct vmx_pages *vmx_pages)
 113 {
 114         GUEST_SYNC(1);
 115         GUEST_SYNC(2);
 116
 117         if (vmx_pages)
 118                 l1_guest_code(vmx_pages);
 119
 120         GUEST_DONE();
 121 }
 122
 123 int main(int argc, char *argv[])
 124 {
 125         struct vmx_pages *vmx_pages = NULL;
 126         vm_vaddr_t vmx_pages_gva = 0;
 127
 128         struct kvm_regs regs1, regs2;
 129         struct kvm_vm *vm;
 130         struct kvm_run *run;
 131         struct kvm_x86_state *state;
 132         struct ucall uc;
 133         int stage;
 134
 135         struct kvm_cpuid_entry2 *entry = kvm_get_supported_cpuid_entry(1);
 136
 137         if (!kvm_check_cap(KVM_CAP_IMMEDIATE_EXIT)) {
 138                 fprintf(stderr, "immediate_exit not available, skipping test\n");
 139                 exit(KSFT_SKIP);
 140         }
 141
 142         /* Create VM */
 143         vm = vm_create_default(VCPU_ID, 0, guest_code);
 144         vcpu_set_cpuid(vm, VCPU_ID, kvm_get_supported_cpuid());
 145         run = vcpu_state(vm, VCPU_ID);
 146
 147         vcpu_regs_get(vm, VCPU_ID, &regs1);
 148
 149         if (kvm_check_cap(KVM_CAP_NESTED_STATE)) {
 150                 vmx_pages = vcpu_alloc_vmx(vm, &vmx_pages_gva);
 151                 vcpu_args_set(vm, VCPU_ID, 1, vmx_pages_gva);
 152         } else {
 153                 printf("will skip nested state checks\n");
 154                 vcpu_args_set(vm, VCPU_ID, 1, 0);
 155         }
 156
 157         for (stage = 1;; stage++) {
 158                 _vcpu_run(vm, VCPU_ID);
 159                 TEST_ASSERT(run->exit_reason == KVM_EXIT_IO,
 160                             "Stage %d: unexpected exit reason: %u (%s),\n",
 161                             stage, run->exit_reason,
 162                             exit_reason_str(run->exit_reason));
 163
 164                 switch (get_ucall(vm, VCPU_ID, &uc)) {
 165                 case UCALL_ABORT:
 166                         TEST_ASSERT(false, "%s at %s:%d", (const char *)uc.args[0],
 167                                     __FILE__, uc.args[1]);
 168                         /* NOT REACHED */
 169                 case UCALL_SYNC:
 170                         break;
 171                 case UCALL_DONE:
 172                         goto done;
 173                 default:
 174                         TEST_ASSERT(false, "Unknown ucall 0x%x.", uc.cmd);
 175                 }
 176
 177                 /* UCALL_SYNC is handled here.  */
 178                 TEST_ASSERT(!strcmp((const char *)uc.args[0], "hello") &&
 179                             uc.args[1] == stage, "Unexpected register values vmexit #%lx, got %lx",
 180                             stage, (ulong)uc.args[1]);
 181
 182                 /*
 183                  * When KVM exits to userspace with KVM_EXIT_IO, KVM guarantees
 184                  * guest state is consistent only after userspace re-enters the
 185                  * kernel with KVM_RUN.  Complete IO prior to migrating state
 186                  * to a new VM.
 187                  */
 188                 vcpu_run_complete_io(vm, VCPU_ID);
 189
 190                 memset(&regs1, 0, sizeof(regs1));
 191                 vcpu_regs_get(vm, VCPU_ID, &regs1);
 192
 193                 state = vcpu_save_state(vm, VCPU_ID);
 194                 kvm_vm_release(vm);
 195
 196                 /* Restore state in a new VM.  */
 197                 kvm_vm_restart(vm, O_RDWR);
 198                 vm_vcpu_add(vm, VCPU_ID, 0, 0);
 199                 vcpu_set_cpuid(vm, VCPU_ID, kvm_get_supported_cpuid());
 200                 vcpu_load_state(vm, VCPU_ID, state);
 201                 run = vcpu_state(vm, VCPU_ID);
 202                 free(state);
 203
 204                 memset(&regs2, 0, sizeof(regs2));
 205                 vcpu_regs_get(vm, VCPU_ID, &regs2);
 206                 TEST_ASSERT(!memcmp(&regs1, &regs2, sizeof(regs2)),
 207                             "Unexpected register values after vcpu_load_state; rdi: %lx rsi: %lx",
 208                             (ulong) regs2.rdi, (ulong) regs2.rsi);
 209         }
 210
 211 done:
 212         kvm_vm_free(vm);
 213 }