1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * KVM_GET/SET_* tests
4  *
5  * Copyright (C) 2018, Red Hat, Inc.
6  *
7  * Tests for vCPU state save/restore, including nested guest state.
8  */
9 #define _GNU_SOURCE /* for program_invocation_short_name */
10 #include <fcntl.h>
11 #include <stdio.h>
12 #include <stdlib.h>
13 #include <string.h>
14 #include <sys/ioctl.h>
15 
16 #include "test_util.h"
17 
18 #include "kvm_util.h"
19 #include "processor.h"
20 #include "vmx.h"
21 
22 #define VCPU_ID		5
23 
l2_guest_code(void)24 void l2_guest_code(void)
25 {
26 	GUEST_SYNC(6);
27 
28         /* Exit to L1 */
29 	vmcall();
30 
31 	/* L1 has now set up a shadow VMCS for us.  */
32 	GUEST_ASSERT(vmreadz(GUEST_RIP) == 0xc0ffee);
33 	GUEST_SYNC(10);
34 	GUEST_ASSERT(vmreadz(GUEST_RIP) == 0xc0ffee);
35 	GUEST_ASSERT(!vmwrite(GUEST_RIP, 0xc0fffee));
36 	GUEST_SYNC(11);
37 	GUEST_ASSERT(vmreadz(GUEST_RIP) == 0xc0fffee);
38 	GUEST_ASSERT(!vmwrite(GUEST_RIP, 0xc0ffffee));
39 	GUEST_SYNC(12);
40 
41 	/* Done, exit to L1 and never come back.  */
42 	vmcall();
43 }
44 
l1_guest_code(struct vmx_pages * vmx_pages)45 void l1_guest_code(struct vmx_pages *vmx_pages)
46 {
47 #define L2_GUEST_STACK_SIZE 64
48         unsigned long l2_guest_stack[L2_GUEST_STACK_SIZE];
49 
50 	GUEST_ASSERT(vmx_pages->vmcs_gpa);
51 	GUEST_ASSERT(prepare_for_vmx_operation(vmx_pages));
52 	GUEST_SYNC(3);
53 	GUEST_ASSERT(load_vmcs(vmx_pages));
54 	GUEST_ASSERT(vmptrstz() == vmx_pages->vmcs_gpa);
55 
56 	GUEST_SYNC(4);
57 	GUEST_ASSERT(vmptrstz() == vmx_pages->vmcs_gpa);
58 
59 	prepare_vmcs(vmx_pages, l2_guest_code,
60 		     &l2_guest_stack[L2_GUEST_STACK_SIZE]);
61 
62 	GUEST_SYNC(5);
63 	GUEST_ASSERT(vmptrstz() == vmx_pages->vmcs_gpa);
64 	GUEST_ASSERT(!vmlaunch());
65 	GUEST_ASSERT(vmptrstz() == vmx_pages->vmcs_gpa);
66 	GUEST_ASSERT(vmreadz(VM_EXIT_REASON) == EXIT_REASON_VMCALL);
67 
68 	/* Check that the launched state is preserved.  */
69 	GUEST_ASSERT(vmlaunch());
70 
71 	GUEST_ASSERT(!vmresume());
72 	GUEST_ASSERT(vmreadz(VM_EXIT_REASON) == EXIT_REASON_VMCALL);
73 
74 	GUEST_SYNC(7);
75 	GUEST_ASSERT(vmreadz(VM_EXIT_REASON) == EXIT_REASON_VMCALL);
76 
77 	GUEST_ASSERT(!vmresume());
78 	GUEST_ASSERT(vmreadz(VM_EXIT_REASON) == EXIT_REASON_VMCALL);
79 
80 	vmwrite(GUEST_RIP, vmreadz(GUEST_RIP) + 3);
81 
82 	vmwrite(SECONDARY_VM_EXEC_CONTROL, SECONDARY_EXEC_SHADOW_VMCS);
83 	vmwrite(VMCS_LINK_POINTER, vmx_pages->shadow_vmcs_gpa);
84 
85 	GUEST_ASSERT(!vmptrld(vmx_pages->shadow_vmcs_gpa));
86 	GUEST_ASSERT(vmlaunch());
87 	GUEST_SYNC(8);
88 	GUEST_ASSERT(vmlaunch());
89 	GUEST_ASSERT(vmresume());
90 
91 	vmwrite(GUEST_RIP, 0xc0ffee);
92 	GUEST_SYNC(9);
93 	GUEST_ASSERT(vmreadz(GUEST_RIP) == 0xc0ffee);
94 
95 	GUEST_ASSERT(!vmptrld(vmx_pages->vmcs_gpa));
96 	GUEST_ASSERT(!vmresume());
97 	GUEST_ASSERT(vmreadz(VM_EXIT_REASON) == EXIT_REASON_VMCALL);
98 
99 	GUEST_ASSERT(!vmptrld(vmx_pages->shadow_vmcs_gpa));
100 	GUEST_ASSERT(vmreadz(GUEST_RIP) == 0xc0ffffee);
101 	GUEST_ASSERT(vmlaunch());
102 	GUEST_ASSERT(vmresume());
103 	GUEST_SYNC(13);
104 	GUEST_ASSERT(vmreadz(GUEST_RIP) == 0xc0ffffee);
105 	GUEST_ASSERT(vmlaunch());
106 	GUEST_ASSERT(vmresume());
107 }
108 
guest_code(struct vmx_pages * vmx_pages)109 void guest_code(struct vmx_pages *vmx_pages)
110 {
111 	GUEST_SYNC(1);
112 	GUEST_SYNC(2);
113 
114 	if (vmx_pages)
115 		l1_guest_code(vmx_pages);
116 
117 	GUEST_DONE();
118 }
119 
main(int argc,char * argv[])120 int main(int argc, char *argv[])
121 {
122 	vm_vaddr_t vmx_pages_gva = 0;
123 
124 	struct kvm_regs regs1, regs2;
125 	struct kvm_vm *vm;
126 	struct kvm_run *run;
127 	struct kvm_x86_state *state;
128 	struct ucall uc;
129 	int stage;
130 
131 	/* Create VM */
132 	vm = vm_create_default(VCPU_ID, 0, guest_code);
133 	vcpu_set_cpuid(vm, VCPU_ID, kvm_get_supported_cpuid());
134 	run = vcpu_state(vm, VCPU_ID);
135 
136 	vcpu_regs_get(vm, VCPU_ID, &regs1);
137 
138 	if (kvm_check_cap(KVM_CAP_NESTED_STATE)) {
139 		vcpu_alloc_vmx(vm, &vmx_pages_gva);
140 		vcpu_args_set(vm, VCPU_ID, 1, vmx_pages_gva);
141 	} else {
142 		printf("will skip nested state checks\n");
143 		vcpu_args_set(vm, VCPU_ID, 1, 0);
144 	}
145 
146 	for (stage = 1;; stage++) {
147 		_vcpu_run(vm, VCPU_ID);
148 		TEST_ASSERT(run->exit_reason == KVM_EXIT_IO,
149 			    "Stage %d: unexpected exit reason: %u (%s),\n",
150 			    stage, run->exit_reason,
151 			    exit_reason_str(run->exit_reason));
152 
153 		switch (get_ucall(vm, VCPU_ID, &uc)) {
154 		case UCALL_ABORT:
155 			TEST_ASSERT(false, "%s at %s:%d", (const char *)uc.args[0],
156 				    __FILE__, uc.args[1]);
157 			/* NOT REACHED */
158 		case UCALL_SYNC:
159 			break;
160 		case UCALL_DONE:
161 			goto done;
162 		default:
163 			TEST_ASSERT(false, "Unknown ucall 0x%x.", uc.cmd);
164 		}
165 
166 		/* UCALL_SYNC is handled here.  */
167 		TEST_ASSERT(!strcmp((const char *)uc.args[0], "hello") &&
168 			    uc.args[1] == stage, "Unexpected register values vmexit #%lx, got %lx",
169 			    stage, (ulong)uc.args[1]);
170 
171 		state = vcpu_save_state(vm, VCPU_ID);
172 		memset(&regs1, 0, sizeof(regs1));
173 		vcpu_regs_get(vm, VCPU_ID, &regs1);
174 
175 		kvm_vm_release(vm);
176 
177 		/* Restore state in a new VM.  */
178 		kvm_vm_restart(vm, O_RDWR);
179 		vm_vcpu_add(vm, VCPU_ID);
180 		vcpu_set_cpuid(vm, VCPU_ID, kvm_get_supported_cpuid());
181 		vcpu_load_state(vm, VCPU_ID, state);
182 		run = vcpu_state(vm, VCPU_ID);
183 		free(state);
184 
185 		memset(&regs2, 0, sizeof(regs2));
186 		vcpu_regs_get(vm, VCPU_ID, &regs2);
187 		TEST_ASSERT(!memcmp(&regs1, &regs2, sizeof(regs2)),
188 			    "Unexpected register values after vcpu_load_state; rdi: %lx rsi: %lx",
189 			    (ulong) regs2.rdi, (ulong) regs2.rsi);
190 	}
191 
192 done:
193 	kvm_vm_free(vm);
194 }
195