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