xref: /openbmc/linux/tools/testing/selftests/kvm/x86_64/state_test.c (revision 4f727ecefefbd180de10e25b3e74c03dce3f1e75)
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 void l2_guest_code(void)
26 {
27 	GUEST_SYNC(6);
28 
29         /* Exit to L1 */
30 	vmcall();
31 
32 	/* L1 has now set up a shadow VMCS for us.  */
33 	GUEST_ASSERT(vmreadz(GUEST_RIP) == 0xc0ffee);
34 	GUEST_SYNC(10);
35 	GUEST_ASSERT(vmreadz(GUEST_RIP) == 0xc0ffee);
36 	GUEST_ASSERT(!vmwrite(GUEST_RIP, 0xc0fffee));
37 	GUEST_SYNC(11);
38 	GUEST_ASSERT(vmreadz(GUEST_RIP) == 0xc0fffee);
39 	GUEST_ASSERT(!vmwrite(GUEST_RIP, 0xc0ffffee));
40 	GUEST_SYNC(12);
41 
42 	/* Done, exit to L1 and never come back.  */
43 	vmcall();
44 }
45 
46 void l1_guest_code(struct vmx_pages *vmx_pages)
47 {
48 #define L2_GUEST_STACK_SIZE 64
49         unsigned long l2_guest_stack[L2_GUEST_STACK_SIZE];
50 
51 	GUEST_ASSERT(vmx_pages->vmcs_gpa);
52 	GUEST_ASSERT(prepare_for_vmx_operation(vmx_pages));
53 	GUEST_SYNC(3);
54 	GUEST_ASSERT(load_vmcs(vmx_pages));
55 	GUEST_ASSERT(vmptrstz() == vmx_pages->vmcs_gpa);
56 
57 	GUEST_SYNC(4);
58 	GUEST_ASSERT(vmptrstz() == vmx_pages->vmcs_gpa);
59 
60 	prepare_vmcs(vmx_pages, l2_guest_code,
61 		     &l2_guest_stack[L2_GUEST_STACK_SIZE]);
62 
63 	GUEST_SYNC(5);
64 	GUEST_ASSERT(vmptrstz() == vmx_pages->vmcs_gpa);
65 	GUEST_ASSERT(!vmlaunch());
66 	GUEST_ASSERT(vmptrstz() == vmx_pages->vmcs_gpa);
67 	GUEST_ASSERT(vmreadz(VM_EXIT_REASON) == EXIT_REASON_VMCALL);
68 
69 	/* Check that the launched state is preserved.  */
70 	GUEST_ASSERT(vmlaunch());
71 
72 	GUEST_ASSERT(!vmresume());
73 	GUEST_ASSERT(vmreadz(VM_EXIT_REASON) == EXIT_REASON_VMCALL);
74 
75 	GUEST_SYNC(7);
76 	GUEST_ASSERT(vmreadz(VM_EXIT_REASON) == EXIT_REASON_VMCALL);
77 
78 	GUEST_ASSERT(!vmresume());
79 	GUEST_ASSERT(vmreadz(VM_EXIT_REASON) == EXIT_REASON_VMCALL);
80 
81 	vmwrite(GUEST_RIP, vmreadz(GUEST_RIP) + 3);
82 
83 	vmwrite(SECONDARY_VM_EXEC_CONTROL, SECONDARY_EXEC_SHADOW_VMCS);
84 	vmwrite(VMCS_LINK_POINTER, vmx_pages->shadow_vmcs_gpa);
85 
86 	GUEST_ASSERT(!vmptrld(vmx_pages->shadow_vmcs_gpa));
87 	GUEST_ASSERT(vmlaunch());
88 	GUEST_SYNC(8);
89 	GUEST_ASSERT(vmlaunch());
90 	GUEST_ASSERT(vmresume());
91 
92 	vmwrite(GUEST_RIP, 0xc0ffee);
93 	GUEST_SYNC(9);
94 	GUEST_ASSERT(vmreadz(GUEST_RIP) == 0xc0ffee);
95 
96 	GUEST_ASSERT(!vmptrld(vmx_pages->vmcs_gpa));
97 	GUEST_ASSERT(!vmresume());
98 	GUEST_ASSERT(vmreadz(VM_EXIT_REASON) == EXIT_REASON_VMCALL);
99 
100 	GUEST_ASSERT(!vmptrld(vmx_pages->shadow_vmcs_gpa));
101 	GUEST_ASSERT(vmreadz(GUEST_RIP) == 0xc0ffffee);
102 	GUEST_ASSERT(vmlaunch());
103 	GUEST_ASSERT(vmresume());
104 	GUEST_SYNC(13);
105 	GUEST_ASSERT(vmreadz(GUEST_RIP) == 0xc0ffffee);
106 	GUEST_ASSERT(vmlaunch());
107 	GUEST_ASSERT(vmresume());
108 }
109 
110 void guest_code(struct vmx_pages *vmx_pages)
111 {
112 	GUEST_SYNC(1);
113 	GUEST_SYNC(2);
114 
115 	if (vmx_pages)
116 		l1_guest_code(vmx_pages);
117 
118 	GUEST_DONE();
119 }
120 
121 int main(int argc, char *argv[])
122 {
123 	vm_vaddr_t vmx_pages_gva = 0;
124 
125 	struct kvm_regs regs1, regs2;
126 	struct kvm_vm *vm;
127 	struct kvm_run *run;
128 	struct kvm_x86_state *state;
129 	struct ucall uc;
130 	int stage;
131 
132 	/* Create VM */
133 	vm = vm_create_default(VCPU_ID, 0, guest_code);
134 	vcpu_set_cpuid(vm, VCPU_ID, kvm_get_supported_cpuid());
135 	run = vcpu_state(vm, VCPU_ID);
136 
137 	vcpu_regs_get(vm, VCPU_ID, &regs1);
138 
139 	if (kvm_check_cap(KVM_CAP_NESTED_STATE)) {
140 		vcpu_alloc_vmx(vm, &vmx_pages_gva);
141 		vcpu_args_set(vm, VCPU_ID, 1, vmx_pages_gva);
142 	} else {
143 		printf("will skip nested state checks\n");
144 		vcpu_args_set(vm, VCPU_ID, 1, 0);
145 	}
146 
147 	for (stage = 1;; stage++) {
148 		_vcpu_run(vm, VCPU_ID);
149 		TEST_ASSERT(run->exit_reason == KVM_EXIT_IO,
150 			    "Stage %d: unexpected exit reason: %u (%s),\n",
151 			    stage, run->exit_reason,
152 			    exit_reason_str(run->exit_reason));
153 
154 		switch (get_ucall(vm, VCPU_ID, &uc)) {
155 		case UCALL_ABORT:
156 			TEST_ASSERT(false, "%s at %s:%d", (const char *)uc.args[0],
157 				    __FILE__, uc.args[1]);
158 			/* NOT REACHED */
159 		case UCALL_SYNC:
160 			break;
161 		case UCALL_DONE:
162 			goto done;
163 		default:
164 			TEST_ASSERT(false, "Unknown ucall 0x%x.", uc.cmd);
165 		}
166 
167 		/* UCALL_SYNC is handled here.  */
168 		TEST_ASSERT(!strcmp((const char *)uc.args[0], "hello") &&
169 			    uc.args[1] == stage, "Unexpected register values vmexit #%lx, got %lx",
170 			    stage, (ulong)uc.args[1]);
171 
172 		state = vcpu_save_state(vm, VCPU_ID);
173 		memset(&regs1, 0, sizeof(regs1));
174 		vcpu_regs_get(vm, VCPU_ID, &regs1);
175 
176 		kvm_vm_release(vm);
177 
178 		/* Restore state in a new VM.  */
179 		kvm_vm_restart(vm, O_RDWR);
180 		vm_vcpu_add(vm, VCPU_ID, 0, 0);
181 		vcpu_set_cpuid(vm, VCPU_ID, kvm_get_supported_cpuid());
182 		vcpu_load_state(vm, VCPU_ID, state);
183 		run = vcpu_state(vm, VCPU_ID);
184 		free(state);
185 
186 		memset(&regs2, 0, sizeof(regs2));
187 		vcpu_regs_get(vm, VCPU_ID, &regs2);
188 		TEST_ASSERT(!memcmp(&regs1, &regs2, sizeof(regs2)),
189 			    "Unexpected register values after vcpu_load_state; rdi: %lx rsi: %lx",
190 			    (ulong) regs2.rdi, (ulong) regs2.rsi);
191 	}
192 
193 done:
194 	kvm_vm_free(vm);
195 }
196