1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (C) 2021, Red Hat Inc.
4 *
5 * Generic tests for KVM CPUID set/get ioctls
6 */
7#include <asm/kvm_para.h>
8#include <linux/kvm_para.h>
9#include <stdint.h>
10
11#include "test_util.h"
12#include "kvm_util.h"
13#include "processor.h"
14
15/* CPUIDs known to differ */
16struct {
17	u32 function;
18	u32 index;
19} mangled_cpuids[] = {
20	/*
21	 * These entries depend on the vCPU's XCR0 register and IA32_XSS MSR,
22	 * which are not controlled for by this test.
23	 */
24	{.function = 0xd, .index = 0},
25	{.function = 0xd, .index = 1},
26};
27
28static void test_guest_cpuids(struct kvm_cpuid2 *guest_cpuid)
29{
30	int i;
31	u32 eax, ebx, ecx, edx;
32
33	for (i = 0; i < guest_cpuid->nent; i++) {
34		__cpuid(guest_cpuid->entries[i].function,
35			guest_cpuid->entries[i].index,
36			&eax, &ebx, &ecx, &edx);
37
38		GUEST_ASSERT_EQ(eax, guest_cpuid->entries[i].eax);
39		GUEST_ASSERT_EQ(ebx, guest_cpuid->entries[i].ebx);
40		GUEST_ASSERT_EQ(ecx, guest_cpuid->entries[i].ecx);
41		GUEST_ASSERT_EQ(edx, guest_cpuid->entries[i].edx);
42	}
43
44}
45
46static void guest_main(struct kvm_cpuid2 *guest_cpuid)
47{
48	GUEST_SYNC(1);
49
50	test_guest_cpuids(guest_cpuid);
51
52	GUEST_SYNC(2);
53
54	GUEST_ASSERT_EQ(this_cpu_property(X86_PROPERTY_MAX_KVM_LEAF), 0x40000001);
55
56	GUEST_DONE();
57}
58
59static bool is_cpuid_mangled(const struct kvm_cpuid_entry2 *entrie)
60{
61	int i;
62
63	for (i = 0; i < sizeof(mangled_cpuids); i++) {
64		if (mangled_cpuids[i].function == entrie->function &&
65		    mangled_cpuids[i].index == entrie->index)
66			return true;
67	}
68
69	return false;
70}
71
72static void compare_cpuids(const struct kvm_cpuid2 *cpuid1,
73			   const struct kvm_cpuid2 *cpuid2)
74{
75	const struct kvm_cpuid_entry2 *e1, *e2;
76	int i;
77
78	TEST_ASSERT(cpuid1->nent == cpuid2->nent,
79		    "CPUID nent mismatch: %d vs. %d", cpuid1->nent, cpuid2->nent);
80
81	for (i = 0; i < cpuid1->nent; i++) {
82		e1 = &cpuid1->entries[i];
83		e2 = &cpuid2->entries[i];
84
85		TEST_ASSERT(e1->function == e2->function &&
86			    e1->index == e2->index && e1->flags == e2->flags,
87			    "CPUID entries[%d] mismtach: 0x%x.%d.%x vs. 0x%x.%d.%x",
88			    i, e1->function, e1->index, e1->flags,
89			    e2->function, e2->index, e2->flags);
90
91		if (is_cpuid_mangled(e1))
92			continue;
93
94		TEST_ASSERT(e1->eax == e2->eax && e1->ebx == e2->ebx &&
95			    e1->ecx == e2->ecx && e1->edx == e2->edx,
96			    "CPUID 0x%x.%x differ: 0x%x:0x%x:0x%x:0x%x vs 0x%x:0x%x:0x%x:0x%x",
97			    e1->function, e1->index,
98			    e1->eax, e1->ebx, e1->ecx, e1->edx,
99			    e2->eax, e2->ebx, e2->ecx, e2->edx);
100	}
101}
102
103static void run_vcpu(struct kvm_vcpu *vcpu, int stage)
104{
105	struct ucall uc;
106
107	vcpu_run(vcpu);
108
109	switch (get_ucall(vcpu, &uc)) {
110	case UCALL_SYNC:
111		TEST_ASSERT(!strcmp((const char *)uc.args[0], "hello") &&
112			    uc.args[1] == stage + 1,
113			    "Stage %d: Unexpected register values vmexit, got %lx",
114			    stage + 1, (ulong)uc.args[1]);
115		return;
116	case UCALL_DONE:
117		return;
118	case UCALL_ABORT:
119		REPORT_GUEST_ASSERT(uc);
120	default:
121		TEST_ASSERT(false, "Unexpected exit: %s",
122			    exit_reason_str(vcpu->run->exit_reason));
123	}
124}
125
126struct kvm_cpuid2 *vcpu_alloc_cpuid(struct kvm_vm *vm, vm_vaddr_t *p_gva, struct kvm_cpuid2 *cpuid)
127{
128	int size = sizeof(*cpuid) + cpuid->nent * sizeof(cpuid->entries[0]);
129	vm_vaddr_t gva = vm_vaddr_alloc(vm, size, KVM_UTIL_MIN_VADDR);
130	struct kvm_cpuid2 *guest_cpuids = addr_gva2hva(vm, gva);
131
132	memcpy(guest_cpuids, cpuid, size);
133
134	*p_gva = gva;
135	return guest_cpuids;
136}
137
138static void set_cpuid_after_run(struct kvm_vcpu *vcpu)
139{
140	struct kvm_cpuid_entry2 *ent;
141	int rc;
142	u32 eax, ebx, x;
143
144	/* Setting unmodified CPUID is allowed */
145	rc = __vcpu_set_cpuid(vcpu);
146	TEST_ASSERT(!rc, "Setting unmodified CPUID after KVM_RUN failed: %d", rc);
147
148	/* Changing CPU features is forbidden */
149	ent = vcpu_get_cpuid_entry(vcpu, 0x7);
150	ebx = ent->ebx;
151	ent->ebx--;
152	rc = __vcpu_set_cpuid(vcpu);
153	TEST_ASSERT(rc, "Changing CPU features should fail");
154	ent->ebx = ebx;
155
156	/* Changing MAXPHYADDR is forbidden */
157	ent = vcpu_get_cpuid_entry(vcpu, 0x80000008);
158	eax = ent->eax;
159	x = eax & 0xff;
160	ent->eax = (eax & ~0xffu) | (x - 1);
161	rc = __vcpu_set_cpuid(vcpu);
162	TEST_ASSERT(rc, "Changing MAXPHYADDR should fail");
163	ent->eax = eax;
164}
165
166static void test_get_cpuid2(struct kvm_vcpu *vcpu)
167{
168	struct kvm_cpuid2 *cpuid = allocate_kvm_cpuid2(vcpu->cpuid->nent + 1);
169	int i, r;
170
171	vcpu_ioctl(vcpu, KVM_GET_CPUID2, cpuid);
172	TEST_ASSERT(cpuid->nent == vcpu->cpuid->nent,
173		    "KVM didn't update nent on success, wanted %u, got %u",
174		    vcpu->cpuid->nent, cpuid->nent);
175
176	for (i = 0; i < vcpu->cpuid->nent; i++) {
177		cpuid->nent = i;
178		r = __vcpu_ioctl(vcpu, KVM_GET_CPUID2, cpuid);
179		TEST_ASSERT(r && errno == E2BIG, KVM_IOCTL_ERROR(KVM_GET_CPUID2, r));
180		TEST_ASSERT(cpuid->nent == i, "KVM modified nent on failure");
181	}
182	free(cpuid);
183}
184
185int main(void)
186{
187	struct kvm_vcpu *vcpu;
188	vm_vaddr_t cpuid_gva;
189	struct kvm_vm *vm;
190	int stage;
191
192	vm = vm_create_with_one_vcpu(&vcpu, guest_main);
193
194	compare_cpuids(kvm_get_supported_cpuid(), vcpu->cpuid);
195
196	vcpu_alloc_cpuid(vm, &cpuid_gva, vcpu->cpuid);
197
198	vcpu_args_set(vcpu, 1, cpuid_gva);
199
200	for (stage = 0; stage < 3; stage++)
201		run_vcpu(vcpu, stage);
202
203	set_cpuid_after_run(vcpu);
204
205	test_get_cpuid2(vcpu);
206
207	kvm_vm_free(vm);
208}
209