1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Test for x86 KVM_CAP_SYNC_REGS
4 *
5 * Copyright (C) 2018, Google LLC.
6 *
7 * Verifies expected behavior of x86 KVM_CAP_SYNC_REGS functionality,
8 * including requesting an invalid register set, updates to/from values
9 * in kvm_run.s.regs when kvm_valid_regs and kvm_dirty_regs are toggled.
10 */
11
12 #define _GNU_SOURCE /* for program_invocation_short_name */
13 #include <fcntl.h>
14 #include <stdio.h>
15 #include <stdlib.h>
16 #include <string.h>
17 #include <sys/ioctl.h>
18
19 #include "test_util.h"
20 #include "kvm_util.h"
21 #include "processor.h"
22
23 #define VCPU_ID 5
24
25 #define UCALL_PIO_PORT ((uint16_t)0x1000)
26
27 /*
28 * ucall is embedded here to protect against compiler reshuffling registers
29 * before calling a function. In this test we only need to get KVM_EXIT_IO
30 * vmexit and preserve RBX, no additional information is needed.
31 */
guest_code(void)32 void guest_code(void)
33 {
34 asm volatile("1: in %[port], %%al\n"
35 "add $0x1, %%rbx\n"
36 "jmp 1b"
37 : : [port] "d" (UCALL_PIO_PORT) : "rax", "rbx");
38 }
39
compare_regs(struct kvm_regs * left,struct kvm_regs * right)40 static void compare_regs(struct kvm_regs *left, struct kvm_regs *right)
41 {
42 #define REG_COMPARE(reg) \
43 TEST_ASSERT(left->reg == right->reg, \
44 "Register " #reg \
45 " values did not match: 0x%llx, 0x%llx\n", \
46 left->reg, right->reg)
47 REG_COMPARE(rax);
48 REG_COMPARE(rbx);
49 REG_COMPARE(rcx);
50 REG_COMPARE(rdx);
51 REG_COMPARE(rsi);
52 REG_COMPARE(rdi);
53 REG_COMPARE(rsp);
54 REG_COMPARE(rbp);
55 REG_COMPARE(r8);
56 REG_COMPARE(r9);
57 REG_COMPARE(r10);
58 REG_COMPARE(r11);
59 REG_COMPARE(r12);
60 REG_COMPARE(r13);
61 REG_COMPARE(r14);
62 REG_COMPARE(r15);
63 REG_COMPARE(rip);
64 REG_COMPARE(rflags);
65 #undef REG_COMPARE
66 }
67
compare_sregs(struct kvm_sregs * left,struct kvm_sregs * right)68 static void compare_sregs(struct kvm_sregs *left, struct kvm_sregs *right)
69 {
70 }
71
compare_vcpu_events(struct kvm_vcpu_events * left,struct kvm_vcpu_events * right)72 static void compare_vcpu_events(struct kvm_vcpu_events *left,
73 struct kvm_vcpu_events *right)
74 {
75 }
76
77 #define TEST_SYNC_FIELDS (KVM_SYNC_X86_REGS|KVM_SYNC_X86_SREGS|KVM_SYNC_X86_EVENTS)
78 #define INVALID_SYNC_FIELD 0x80000000
79
main(int argc,char * argv[])80 int main(int argc, char *argv[])
81 {
82 struct kvm_vm *vm;
83 struct kvm_run *run;
84 struct kvm_regs regs;
85 struct kvm_sregs sregs;
86 struct kvm_vcpu_events events;
87 int rv, cap;
88
89 /* Tell stdout not to buffer its content */
90 setbuf(stdout, NULL);
91
92 cap = kvm_check_cap(KVM_CAP_SYNC_REGS);
93 if ((cap & TEST_SYNC_FIELDS) != TEST_SYNC_FIELDS) {
94 fprintf(stderr, "KVM_CAP_SYNC_REGS not supported, skipping test\n");
95 exit(KSFT_SKIP);
96 }
97 if ((cap & INVALID_SYNC_FIELD) != 0) {
98 fprintf(stderr, "The \"invalid\" field is not invalid, skipping test\n");
99 exit(KSFT_SKIP);
100 }
101
102 /* Create VM */
103 vm = vm_create_default(VCPU_ID, 0, guest_code);
104
105 run = vcpu_state(vm, VCPU_ID);
106
107 /* Request reading invalid register set from VCPU. */
108 run->kvm_valid_regs = INVALID_SYNC_FIELD;
109 rv = _vcpu_run(vm, VCPU_ID);
110 TEST_ASSERT(rv < 0 && errno == EINVAL,
111 "Invalid kvm_valid_regs did not cause expected KVM_RUN error: %d\n",
112 rv);
113 vcpu_state(vm, VCPU_ID)->kvm_valid_regs = 0;
114
115 run->kvm_valid_regs = INVALID_SYNC_FIELD | TEST_SYNC_FIELDS;
116 rv = _vcpu_run(vm, VCPU_ID);
117 TEST_ASSERT(rv < 0 && errno == EINVAL,
118 "Invalid kvm_valid_regs did not cause expected KVM_RUN error: %d\n",
119 rv);
120 vcpu_state(vm, VCPU_ID)->kvm_valid_regs = 0;
121
122 /* Request setting invalid register set into VCPU. */
123 run->kvm_dirty_regs = INVALID_SYNC_FIELD;
124 rv = _vcpu_run(vm, VCPU_ID);
125 TEST_ASSERT(rv < 0 && errno == EINVAL,
126 "Invalid kvm_dirty_regs did not cause expected KVM_RUN error: %d\n",
127 rv);
128 vcpu_state(vm, VCPU_ID)->kvm_dirty_regs = 0;
129
130 run->kvm_dirty_regs = INVALID_SYNC_FIELD | TEST_SYNC_FIELDS;
131 rv = _vcpu_run(vm, VCPU_ID);
132 TEST_ASSERT(rv < 0 && errno == EINVAL,
133 "Invalid kvm_dirty_regs did not cause expected KVM_RUN error: %d\n",
134 rv);
135 vcpu_state(vm, VCPU_ID)->kvm_dirty_regs = 0;
136
137 /* Request and verify all valid register sets. */
138 /* TODO: BUILD TIME CHECK: TEST_ASSERT(KVM_SYNC_X86_NUM_FIELDS != 3); */
139 run->kvm_valid_regs = TEST_SYNC_FIELDS;
140 rv = _vcpu_run(vm, VCPU_ID);
141 TEST_ASSERT(run->exit_reason == KVM_EXIT_IO,
142 "Unexpected exit reason: %u (%s),\n",
143 run->exit_reason,
144 exit_reason_str(run->exit_reason));
145
146 vcpu_regs_get(vm, VCPU_ID, ®s);
147 compare_regs(®s, &run->s.regs.regs);
148
149 vcpu_sregs_get(vm, VCPU_ID, &sregs);
150 compare_sregs(&sregs, &run->s.regs.sregs);
151
152 vcpu_events_get(vm, VCPU_ID, &events);
153 compare_vcpu_events(&events, &run->s.regs.events);
154
155 /* Set and verify various register values. */
156 run->s.regs.regs.rbx = 0xBAD1DEA;
157 run->s.regs.sregs.apic_base = 1 << 11;
158 /* TODO run->s.regs.events.XYZ = ABC; */
159
160 run->kvm_valid_regs = TEST_SYNC_FIELDS;
161 run->kvm_dirty_regs = KVM_SYNC_X86_REGS | KVM_SYNC_X86_SREGS;
162 rv = _vcpu_run(vm, VCPU_ID);
163 TEST_ASSERT(run->exit_reason == KVM_EXIT_IO,
164 "Unexpected exit reason: %u (%s),\n",
165 run->exit_reason,
166 exit_reason_str(run->exit_reason));
167 TEST_ASSERT(run->s.regs.regs.rbx == 0xBAD1DEA + 1,
168 "rbx sync regs value incorrect 0x%llx.",
169 run->s.regs.regs.rbx);
170 TEST_ASSERT(run->s.regs.sregs.apic_base == 1 << 11,
171 "apic_base sync regs value incorrect 0x%llx.",
172 run->s.regs.sregs.apic_base);
173
174 vcpu_regs_get(vm, VCPU_ID, ®s);
175 compare_regs(®s, &run->s.regs.regs);
176
177 vcpu_sregs_get(vm, VCPU_ID, &sregs);
178 compare_sregs(&sregs, &run->s.regs.sregs);
179
180 vcpu_events_get(vm, VCPU_ID, &events);
181 compare_vcpu_events(&events, &run->s.regs.events);
182
183 /* Clear kvm_dirty_regs bits, verify new s.regs values are
184 * overwritten with existing guest values.
185 */
186 run->kvm_valid_regs = TEST_SYNC_FIELDS;
187 run->kvm_dirty_regs = 0;
188 run->s.regs.regs.rbx = 0xDEADBEEF;
189 rv = _vcpu_run(vm, VCPU_ID);
190 TEST_ASSERT(run->exit_reason == KVM_EXIT_IO,
191 "Unexpected exit reason: %u (%s),\n",
192 run->exit_reason,
193 exit_reason_str(run->exit_reason));
194 TEST_ASSERT(run->s.regs.regs.rbx != 0xDEADBEEF,
195 "rbx sync regs value incorrect 0x%llx.",
196 run->s.regs.regs.rbx);
197
198 /* Clear kvm_valid_regs bits and kvm_dirty_bits.
199 * Verify s.regs values are not overwritten with existing guest values
200 * and that guest values are not overwritten with kvm_sync_regs values.
201 */
202 run->kvm_valid_regs = 0;
203 run->kvm_dirty_regs = 0;
204 run->s.regs.regs.rbx = 0xAAAA;
205 regs.rbx = 0xBAC0;
206 vcpu_regs_set(vm, VCPU_ID, ®s);
207 rv = _vcpu_run(vm, VCPU_ID);
208 TEST_ASSERT(run->exit_reason == KVM_EXIT_IO,
209 "Unexpected exit reason: %u (%s),\n",
210 run->exit_reason,
211 exit_reason_str(run->exit_reason));
212 TEST_ASSERT(run->s.regs.regs.rbx == 0xAAAA,
213 "rbx sync regs value incorrect 0x%llx.",
214 run->s.regs.regs.rbx);
215 vcpu_regs_get(vm, VCPU_ID, ®s);
216 TEST_ASSERT(regs.rbx == 0xBAC0 + 1,
217 "rbx guest value incorrect 0x%llx.",
218 regs.rbx);
219
220 /* Clear kvm_valid_regs bits. Verify s.regs values are not overwritten
221 * with existing guest values but that guest values are overwritten
222 * with kvm_sync_regs values.
223 */
224 run->kvm_valid_regs = 0;
225 run->kvm_dirty_regs = TEST_SYNC_FIELDS;
226 run->s.regs.regs.rbx = 0xBBBB;
227 rv = _vcpu_run(vm, VCPU_ID);
228 TEST_ASSERT(run->exit_reason == KVM_EXIT_IO,
229 "Unexpected exit reason: %u (%s),\n",
230 run->exit_reason,
231 exit_reason_str(run->exit_reason));
232 TEST_ASSERT(run->s.regs.regs.rbx == 0xBBBB,
233 "rbx sync regs value incorrect 0x%llx.",
234 run->s.regs.regs.rbx);
235 vcpu_regs_get(vm, VCPU_ID, ®s);
236 TEST_ASSERT(regs.rbx == 0xBBBB + 1,
237 "rbx guest value incorrect 0x%llx.",
238 regs.rbx);
239
240 kvm_vm_free(vm);
241
242 return 0;
243 }
244