tools/testing/selftests/kvm/x86_64/cr4_cpuid_sync_test.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * CR4 and CPUID sync test
   4  *
   5  * Copyright 2018, Red Hat, Inc. and/or its affiliates.
   6  *
   7  * Author:
   8  *   Wei Huang <wei@redhat.com>
   9  */
  10
  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
  22 static inline bool cr4_cpuid_is_sync(void)
  23 {
  24         uint64_t cr4 = get_cr4();
  25
  26         return (this_cpu_has(X86_FEATURE_OSXSAVE) == !!(cr4 & X86_CR4_OSXSAVE));
  27 }
  28
  29 static void guest_code(void)
  30 {
  31         uint64_t cr4;
  32
  33         /* turn on CR4.OSXSAVE */
  34         cr4 = get_cr4();
  35         cr4 |= X86_CR4_OSXSAVE;
  36         set_cr4(cr4);
  37
  38         /* verify CR4.OSXSAVE == CPUID.OSXSAVE */
  39         GUEST_ASSERT(cr4_cpuid_is_sync());
  40
  41         /* notify hypervisor to change CR4 */
  42         GUEST_SYNC(0);
  43
  44         /* check again */
  45         GUEST_ASSERT(cr4_cpuid_is_sync());
  46
  47         GUEST_DONE();
  48 }
  49
  50 int main(int argc, char *argv[])
  51 {
  52         struct kvm_vcpu *vcpu;
  53         struct kvm_vm *vm;
  54         struct kvm_sregs sregs;
  55         struct ucall uc;
  56
  57         TEST_REQUIRE(kvm_cpu_has(X86_FEATURE_XSAVE));
  58
  59         vm = vm_create_with_one_vcpu(&vcpu, guest_code);
  60
  61         while (1) {
  62                 vcpu_run(vcpu);
  63                 TEST_ASSERT_KVM_EXIT_REASON(vcpu, KVM_EXIT_IO);
  64
  65                 switch (get_ucall(vcpu, &uc)) {
  66                 case UCALL_SYNC:
  67                         /* emulate hypervisor clearing CR4.OSXSAVE */
  68                         vcpu_sregs_get(vcpu, &sregs);
  69                         sregs.cr4 &= ~X86_CR4_OSXSAVE;
  70                         vcpu_sregs_set(vcpu, &sregs);
  71                         break;
  72                 case UCALL_ABORT:
  73                         REPORT_GUEST_ASSERT(uc);
  74                         break;
  75                 case UCALL_DONE:
  76                         goto done;
  77                 default:
  78                         TEST_FAIL("Unknown ucall %lu", uc.cmd);
  79                 }
  80         }
  81
  82 done:
  83         kvm_vm_free(vm);
  84         return 0;
  85 }