1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright (C) 2018, Red Hat, Inc.
4 *
5 * Tests for SMM.
6 */
7 #include <fcntl.h>
8 #include <stdio.h>
9 #include <stdlib.h>
10 #include <stdint.h>
11 #include <string.h>
12 #include <sys/ioctl.h>
13
14 #include "test_util.h"
15
16 #include "kvm_util.h"
17
18 #include "vmx.h"
19 #include "svm_util.h"
20
21 #define SMRAM_SIZE 65536
22 #define SMRAM_MEMSLOT ((1 << 16) | 1)
23 #define SMRAM_PAGES (SMRAM_SIZE / PAGE_SIZE)
24 #define SMRAM_GPA 0x1000000
25 #define SMRAM_STAGE 0xfe
26
27 #define STR(x) #x
28 #define XSTR(s) STR(s)
29
30 #define SYNC_PORT 0xe
31 #define DONE 0xff
32
33 /*
34 * This is compiled as normal 64-bit code, however, SMI handler is executed
35 * in real-address mode. To stay simple we're limiting ourselves to a mode
36 * independent subset of asm here.
37 * SMI handler always report back fixed stage SMRAM_STAGE.
38 */
39 uint8_t smi_handler[] = {
40 0xb0, SMRAM_STAGE, /* mov $SMRAM_STAGE, %al */
41 0xe4, SYNC_PORT, /* in $SYNC_PORT, %al */
42 0x0f, 0xaa, /* rsm */
43 };
44
45 static inline void sync_with_host(uint64_t phase)
46 {
47 asm volatile("in $" XSTR(SYNC_PORT)", %%al \n"
48 : "+a" (phase));
49 }
50
51 static void self_smi(void)
52 {
53 x2apic_write_reg(APIC_ICR,
54 APIC_DEST_SELF | APIC_INT_ASSERT | APIC_DM_SMI);
55 }
56
57 static void l2_guest_code(void)
58 {
59 sync_with_host(8);
60
61 sync_with_host(10);
62
63 vmcall();
64 }
65
66 static void guest_code(void *arg)
67 {
68 #define L2_GUEST_STACK_SIZE 64
69 unsigned long l2_guest_stack[L2_GUEST_STACK_SIZE];
70 uint64_t apicbase = rdmsr(MSR_IA32_APICBASE);
71 struct svm_test_data *svm = arg;
72 struct vmx_pages *vmx_pages = arg;
73
74 sync_with_host(1);
75
76 wrmsr(MSR_IA32_APICBASE, apicbase | X2APIC_ENABLE);
77
78 sync_with_host(2);
79
80 self_smi();
81
82 sync_with_host(4);
83
84 if (arg) {
85 if (this_cpu_has(X86_FEATURE_SVM)) {
86 generic_svm_setup(svm, l2_guest_code,
87 &l2_guest_stack[L2_GUEST_STACK_SIZE]);
88 } else {
89 GUEST_ASSERT(prepare_for_vmx_operation(vmx_pages));
90 GUEST_ASSERT(load_vmcs(vmx_pages));
91 prepare_vmcs(vmx_pages, l2_guest_code,
92 &l2_guest_stack[L2_GUEST_STACK_SIZE]);
93 }
94
95 sync_with_host(5);
96
97 self_smi();
98
99 sync_with_host(7);
100
101 if (this_cpu_has(X86_FEATURE_SVM)) {
102 run_guest(svm->vmcb, svm->vmcb_gpa);
103 run_guest(svm->vmcb, svm->vmcb_gpa);
104 } else {
105 vmlaunch();
106 vmresume();
107 }
108
109 /* Stages 8-11 are eaten by SMM (SMRAM_STAGE reported instead) */
110 sync_with_host(12);
111 }
112
113 sync_with_host(DONE);
114 }
115
116 void inject_smi(struct kvm_vcpu *vcpu)
117 {
118 struct kvm_vcpu_events events;
119
120 vcpu_events_get(vcpu, &events);
121
122 events.smi.pending = 1;
123 events.flags |= KVM_VCPUEVENT_VALID_SMM;
124
125 vcpu_events_set(vcpu, &events);
126 }
127
128 int main(int argc, char *argv[])
129 {
130 vm_vaddr_t nested_gva = 0;
131
132 struct kvm_vcpu *vcpu;
133 struct kvm_regs regs;
134 struct kvm_vm *vm;
135 struct kvm_x86_state *state;
136 int stage, stage_reported;
137
138 TEST_REQUIRE(kvm_has_cap(KVM_CAP_X86_SMM));
139
140 /* Create VM */
141 vm = vm_create_with_one_vcpu(&vcpu, guest_code);
142
143 vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS, SMRAM_GPA,
144 SMRAM_MEMSLOT, SMRAM_PAGES, 0);
145 TEST_ASSERT(vm_phy_pages_alloc(vm, SMRAM_PAGES, SMRAM_GPA, SMRAM_MEMSLOT)
146 == SMRAM_GPA, "could not allocate guest physical addresses?");
147
148 memset(addr_gpa2hva(vm, SMRAM_GPA), 0x0, SMRAM_SIZE);
149 memcpy(addr_gpa2hva(vm, SMRAM_GPA) + 0x8000, smi_handler,
150 sizeof(smi_handler));
151
152 vcpu_set_msr(vcpu, MSR_IA32_SMBASE, SMRAM_GPA);
153
154 if (kvm_has_cap(KVM_CAP_NESTED_STATE)) {
155 if (kvm_cpu_has(X86_FEATURE_SVM))
156 vcpu_alloc_svm(vm, &nested_gva);
157 else if (kvm_cpu_has(X86_FEATURE_VMX))
158 vcpu_alloc_vmx(vm, &nested_gva);
159 }
160
161 if (!nested_gva)
162 pr_info("will skip SMM test with VMX enabled\n");
163
164 vcpu_args_set(vcpu, 1, nested_gva);
165
166 for (stage = 1;; stage++) {
167 vcpu_run(vcpu);
168 TEST_ASSERT_KVM_EXIT_REASON(vcpu, KVM_EXIT_IO);
169
170 memset(®s, 0, sizeof(regs));
171 vcpu_regs_get(vcpu, ®s);
172
173 stage_reported = regs.rax & 0xff;
174
175 if (stage_reported == DONE)
176 goto done;
177
178 TEST_ASSERT(stage_reported == stage ||
179 stage_reported == SMRAM_STAGE,
180 "Unexpected stage: #%x, got %x",
181 stage, stage_reported);
182
183 /*
184 * Enter SMM during L2 execution and check that we correctly
185 * return from it. Do not perform save/restore while in SMM yet.
186 */
187 if (stage == 8) {
188 inject_smi(vcpu);
189 continue;
190 }
191
192 /*
193 * Perform save/restore while the guest is in SMM triggered
194 * during L2 execution.
195 */
196 if (stage == 10)
197 inject_smi(vcpu);
198
199 state = vcpu_save_state(vcpu);
200 kvm_vm_release(vm);
201
202 vcpu = vm_recreate_with_one_vcpu(vm);
203 vcpu_load_state(vcpu, state);
204 kvm_x86_state_cleanup(state);
205 }
206
207 done:
208 kvm_vm_free(vm);
209 }
210
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