1 /*
2  * KVM_GET/SET_* tests
3  *
4  * Copyright (C) 2018, Red Hat, Inc.
5  *
6  * This work is licensed under the terms of the GNU GPL, version 2.
7  *
8  * Tests for vCPU state save/restore, including nested guest state.
9  */
10 #define _GNU_SOURCE /* for program_invocation_short_name */
11 #include <fcntl.h>
12 #include <stdio.h>
13 #include <stdlib.h>
14 #include <string.h>
15 #include <sys/ioctl.h>
16 
17 #include "test_util.h"
18 
19 #include "kvm_util.h"
20 #include "processor.h"
21 #include "vmx.h"
22 
23 #define VCPU_ID		5
24 
25 static bool have_nested_state;
26 
27 void l2_guest_code(void)
28 {
29 	GUEST_SYNC(6);
30 
31         /* Exit to L1 */
32 	vmcall();
33 
34 	/* L1 has now set up a shadow VMCS for us.  */
35 	GUEST_ASSERT(vmreadz(GUEST_RIP) == 0xc0ffee);
36 	GUEST_SYNC(10);
37 	GUEST_ASSERT(vmreadz(GUEST_RIP) == 0xc0ffee);
38 	GUEST_ASSERT(!vmwrite(GUEST_RIP, 0xc0fffee));
39 	GUEST_SYNC(11);
40 	GUEST_ASSERT(vmreadz(GUEST_RIP) == 0xc0fffee);
41 	GUEST_ASSERT(!vmwrite(GUEST_RIP, 0xc0ffffee));
42 	GUEST_SYNC(12);
43 
44 	/* Done, exit to L1 and never come back.  */
45 	vmcall();
46 }
47 
48 void l1_guest_code(struct vmx_pages *vmx_pages)
49 {
50 #define L2_GUEST_STACK_SIZE 64
51         unsigned long l2_guest_stack[L2_GUEST_STACK_SIZE];
52 
53 	GUEST_ASSERT(vmx_pages->vmcs_gpa);
54 	GUEST_ASSERT(prepare_for_vmx_operation(vmx_pages));
55 	GUEST_SYNC(3);
56 	GUEST_ASSERT(load_vmcs(vmx_pages));
57 	GUEST_ASSERT(vmptrstz() == vmx_pages->vmcs_gpa);
58 
59 	GUEST_SYNC(4);
60 	GUEST_ASSERT(vmptrstz() == vmx_pages->vmcs_gpa);
61 
62 	prepare_vmcs(vmx_pages, l2_guest_code,
63 		     &l2_guest_stack[L2_GUEST_STACK_SIZE]);
64 
65 	GUEST_SYNC(5);
66 	GUEST_ASSERT(vmptrstz() == vmx_pages->vmcs_gpa);
67 	GUEST_ASSERT(!vmlaunch());
68 	GUEST_ASSERT(vmptrstz() == vmx_pages->vmcs_gpa);
69 	GUEST_ASSERT(vmreadz(VM_EXIT_REASON) == EXIT_REASON_VMCALL);
70 
71 	/* Check that the launched state is preserved.  */
72 	GUEST_ASSERT(vmlaunch());
73 
74 	GUEST_ASSERT(!vmresume());
75 	GUEST_ASSERT(vmreadz(VM_EXIT_REASON) == EXIT_REASON_VMCALL);
76 
77 	GUEST_SYNC(7);
78 	GUEST_ASSERT(vmreadz(VM_EXIT_REASON) == EXIT_REASON_VMCALL);
79 
80 	GUEST_ASSERT(!vmresume());
81 	GUEST_ASSERT(vmreadz(VM_EXIT_REASON) == EXIT_REASON_VMCALL);
82 
83 	vmwrite(GUEST_RIP, vmreadz(GUEST_RIP) + 3);
84 
85 	vmwrite(SECONDARY_VM_EXEC_CONTROL, SECONDARY_EXEC_SHADOW_VMCS);
86 	vmwrite(VMCS_LINK_POINTER, vmx_pages->shadow_vmcs_gpa);
87 
88 	GUEST_ASSERT(!vmptrld(vmx_pages->shadow_vmcs_gpa));
89 	GUEST_ASSERT(vmlaunch());
90 	GUEST_SYNC(8);
91 	GUEST_ASSERT(vmlaunch());
92 	GUEST_ASSERT(vmresume());
93 
94 	vmwrite(GUEST_RIP, 0xc0ffee);
95 	GUEST_SYNC(9);
96 	GUEST_ASSERT(vmreadz(GUEST_RIP) == 0xc0ffee);
97 
98 	GUEST_ASSERT(!vmptrld(vmx_pages->vmcs_gpa));
99 	GUEST_ASSERT(!vmresume());
100 	GUEST_ASSERT(vmreadz(VM_EXIT_REASON) == EXIT_REASON_VMCALL);
101 
102 	GUEST_ASSERT(!vmptrld(vmx_pages->shadow_vmcs_gpa));
103 	GUEST_ASSERT(vmreadz(GUEST_RIP) == 0xc0ffffee);
104 	GUEST_ASSERT(vmlaunch());
105 	GUEST_ASSERT(vmresume());
106 	GUEST_SYNC(13);
107 	GUEST_ASSERT(vmreadz(GUEST_RIP) == 0xc0ffffee);
108 	GUEST_ASSERT(vmlaunch());
109 	GUEST_ASSERT(vmresume());
110 }
111 
112 void guest_code(struct vmx_pages *vmx_pages)
113 {
114 	GUEST_SYNC(1);
115 	GUEST_SYNC(2);
116 
117 	if (vmx_pages)
118 		l1_guest_code(vmx_pages);
119 
120 	GUEST_DONE();
121 }
122 
123 int main(int argc, char *argv[])
124 {
125 	struct vmx_pages *vmx_pages = NULL;
126 	vm_vaddr_t vmx_pages_gva = 0;
127 
128 	struct kvm_regs regs1, regs2;
129 	struct kvm_vm *vm;
130 	struct kvm_run *run;
131 	struct kvm_x86_state *state;
132 	struct ucall uc;
133 	int stage;
134 
135 	struct kvm_cpuid_entry2 *entry = kvm_get_supported_cpuid_entry(1);
136 
137 	/* Create VM */
138 	vm = vm_create_default(VCPU_ID, 0, guest_code);
139 	vcpu_set_cpuid(vm, VCPU_ID, kvm_get_supported_cpuid());
140 	run = vcpu_state(vm, VCPU_ID);
141 
142 	vcpu_regs_get(vm, VCPU_ID, &regs1);
143 
144 	if (kvm_check_cap(KVM_CAP_NESTED_STATE)) {
145 		vmx_pages = vcpu_alloc_vmx(vm, &vmx_pages_gva);
146 		vcpu_args_set(vm, VCPU_ID, 1, vmx_pages_gva);
147 	} else {
148 		printf("will skip nested state checks\n");
149 		vcpu_args_set(vm, VCPU_ID, 1, 0);
150 	}
151 
152 	for (stage = 1;; stage++) {
153 		_vcpu_run(vm, VCPU_ID);
154 		TEST_ASSERT(run->exit_reason == KVM_EXIT_IO,
155 			    "Stage %d: unexpected exit reason: %u (%s),\n",
156 			    stage, run->exit_reason,
157 			    exit_reason_str(run->exit_reason));
158 
159 		switch (get_ucall(vm, VCPU_ID, &uc)) {
160 		case UCALL_ABORT:
161 			TEST_ASSERT(false, "%s at %s:%d", (const char *)uc.args[0],
162 				    __FILE__, uc.args[1]);
163 			/* NOT REACHED */
164 		case UCALL_SYNC:
165 			break;
166 		case UCALL_DONE:
167 			goto done;
168 		default:
169 			TEST_ASSERT(false, "Unknown ucall 0x%x.", uc.cmd);
170 		}
171 
172 		/* UCALL_SYNC is handled here.  */
173 		TEST_ASSERT(!strcmp((const char *)uc.args[0], "hello") &&
174 			    uc.args[1] == stage, "Unexpected register values vmexit #%lx, got %lx",
175 			    stage, (ulong)uc.args[1]);
176 
177 		state = vcpu_save_state(vm, VCPU_ID);
178 		memset(&regs1, 0, sizeof(regs1));
179 		vcpu_regs_get(vm, VCPU_ID, &regs1);
180 
181 		kvm_vm_release(vm);
182 
183 		/* Restore state in a new VM.  */
184 		kvm_vm_restart(vm, O_RDWR);
185 		vm_vcpu_add(vm, VCPU_ID, 0, 0);
186 		vcpu_set_cpuid(vm, VCPU_ID, kvm_get_supported_cpuid());
187 		vcpu_load_state(vm, VCPU_ID, state);
188 		run = vcpu_state(vm, VCPU_ID);
189 		free(state);
190 
191 		memset(&regs2, 0, sizeof(regs2));
192 		vcpu_regs_get(vm, VCPU_ID, &regs2);
193 		TEST_ASSERT(!memcmp(&regs1, &regs2, sizeof(regs2)),
194 			    "Unexpected register values after vcpu_load_state; rdi: %lx rsi: %lx",
195 			    (ulong) regs2.rdi, (ulong) regs2.rsi);
196 	}
197 
198 done:
199 	kvm_vm_free(vm);
200 }
201