1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Test for x86 KVM_CAP_MSR_PLATFORM_INFO
4 *
5 * Copyright (C) 2018, Google LLC.
6 *
7 * This work is licensed under the terms of the GNU GPL, version 2.
8 *
9 * Verifies expected behavior of controlling guest access to
10 * MSR_PLATFORM_INFO.
11 */
12
13 #define _GNU_SOURCE /* for program_invocation_short_name */
14 #include <fcntl.h>
15 #include <stdio.h>
16 #include <stdlib.h>
17 #include <string.h>
18 #include <sys/ioctl.h>
19
20 #include "test_util.h"
21 #include "kvm_util.h"
22 #include "processor.h"
23
24 #define VCPU_ID 0
25 #define MSR_PLATFORM_INFO_MAX_TURBO_RATIO 0xff00
26
guest_code(void)27 static void guest_code(void)
28 {
29 uint64_t msr_platform_info;
30
31 for (;;) {
32 msr_platform_info = rdmsr(MSR_PLATFORM_INFO);
33 GUEST_SYNC(msr_platform_info);
34 asm volatile ("inc %r11");
35 }
36 }
37
set_msr_platform_info_enabled(struct kvm_vm * vm,bool enable)38 static void set_msr_platform_info_enabled(struct kvm_vm *vm, bool enable)
39 {
40 struct kvm_enable_cap cap = {};
41
42 cap.cap = KVM_CAP_MSR_PLATFORM_INFO;
43 cap.flags = 0;
44 cap.args[0] = (int)enable;
45 vm_enable_cap(vm, &cap);
46 }
47
test_msr_platform_info_enabled(struct kvm_vm * vm)48 static void test_msr_platform_info_enabled(struct kvm_vm *vm)
49 {
50 struct kvm_run *run = vcpu_state(vm, VCPU_ID);
51 struct ucall uc;
52
53 set_msr_platform_info_enabled(vm, true);
54 vcpu_run(vm, VCPU_ID);
55 TEST_ASSERT(run->exit_reason == KVM_EXIT_IO,
56 "Exit_reason other than KVM_EXIT_IO: %u (%s),\n",
57 run->exit_reason,
58 exit_reason_str(run->exit_reason));
59 get_ucall(vm, VCPU_ID, &uc);
60 TEST_ASSERT(uc.cmd == UCALL_SYNC,
61 "Received ucall other than UCALL_SYNC: %u\n",
62 ucall);
63 TEST_ASSERT((uc.args[1] & MSR_PLATFORM_INFO_MAX_TURBO_RATIO) ==
64 MSR_PLATFORM_INFO_MAX_TURBO_RATIO,
65 "Expected MSR_PLATFORM_INFO to have max turbo ratio mask: %i.",
66 MSR_PLATFORM_INFO_MAX_TURBO_RATIO);
67 }
68
test_msr_platform_info_disabled(struct kvm_vm * vm)69 static void test_msr_platform_info_disabled(struct kvm_vm *vm)
70 {
71 struct kvm_run *run = vcpu_state(vm, VCPU_ID);
72
73 set_msr_platform_info_enabled(vm, false);
74 vcpu_run(vm, VCPU_ID);
75 TEST_ASSERT(run->exit_reason == KVM_EXIT_SHUTDOWN,
76 "Exit_reason other than KVM_EXIT_SHUTDOWN: %u (%s)\n",
77 run->exit_reason,
78 exit_reason_str(run->exit_reason));
79 }
80
main(int argc,char * argv[])81 int main(int argc, char *argv[])
82 {
83 struct kvm_vm *vm;
84 int rv;
85 uint64_t msr_platform_info;
86
87 /* Tell stdout not to buffer its content */
88 setbuf(stdout, NULL);
89
90 rv = kvm_check_cap(KVM_CAP_MSR_PLATFORM_INFO);
91 if (!rv) {
92 fprintf(stderr,
93 "KVM_CAP_MSR_PLATFORM_INFO not supported, skip test\n");
94 exit(KSFT_SKIP);
95 }
96
97 vm = vm_create_default(VCPU_ID, 0, guest_code);
98
99 msr_platform_info = vcpu_get_msr(vm, VCPU_ID, MSR_PLATFORM_INFO);
100 vcpu_set_msr(vm, VCPU_ID, MSR_PLATFORM_INFO,
101 msr_platform_info | MSR_PLATFORM_INFO_MAX_TURBO_RATIO);
102 test_msr_platform_info_enabled(vm);
103 test_msr_platform_info_disabled(vm);
104 vcpu_set_msr(vm, VCPU_ID, MSR_PLATFORM_INFO, msr_platform_info);
105
106 kvm_vm_free(vm);
107
108 return 0;
109 }
110