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 }
86
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