1 // SPDX-License-Identifier: GPL-2.0-only
2 #include <fcntl.h>
3 #include <stdio.h>
4 #include <stdlib.h>
5 #include <string.h>
6 #include <sys/ioctl.h>
7 #include <math.h>
8 
9 #include "test_util.h"
10 #include "kvm_util.h"
11 #include "processor.h"
12 #include "svm_util.h"
13 #include "linux/psp-sev.h"
14 #include "sev.h"
15 
16 
17 #define XFEATURE_MASK_X87_AVX (XFEATURE_MASK_FP | XFEATURE_MASK_SSE | XFEATURE_MASK_YMM)
18 
guest_sev_es_code(void)19 static void guest_sev_es_code(void)
20 {
21 	/* TODO: Check CPUID after GHCB-based hypercall support is added. */
22 	GUEST_ASSERT(rdmsr(MSR_AMD64_SEV) & MSR_AMD64_SEV_ENABLED);
23 	GUEST_ASSERT(rdmsr(MSR_AMD64_SEV) & MSR_AMD64_SEV_ES_ENABLED);
24 
25 	/*
26 	 * TODO: Add GHCB and ucall support for SEV-ES guests.  For now, simply
27 	 * force "termination" to signal "done" via the GHCB MSR protocol.
28 	 */
29 	wrmsr(MSR_AMD64_SEV_ES_GHCB, GHCB_MSR_TERM_REQ);
30 	__asm__ __volatile__("rep; vmmcall");
31 }
32 
guest_sev_code(void)33 static void guest_sev_code(void)
34 {
35 	GUEST_ASSERT(this_cpu_has(X86_FEATURE_SEV));
36 	GUEST_ASSERT(rdmsr(MSR_AMD64_SEV) & MSR_AMD64_SEV_ENABLED);
37 
38 	GUEST_DONE();
39 }
40 
41 /* Stash state passed via VMSA before any compiled code runs.  */
42 extern void guest_code_xsave(void);
43 asm("guest_code_xsave:\n"
44     "mov $" __stringify(XFEATURE_MASK_X87_AVX) ", %eax\n"
45     "xor %edx, %edx\n"
46     "xsave (%rdi)\n"
47     "jmp guest_sev_es_code");
48 
compare_xsave(u8 * from_host,u8 * from_guest)49 static void compare_xsave(u8 *from_host, u8 *from_guest)
50 {
51 	int i;
52 	bool bad = false;
53 	for (i = 0; i < 4095; i++) {
54 		if (from_host[i] != from_guest[i]) {
55 			printf("mismatch at %u | %02hhx %02hhx\n",
56 			       i, from_host[i], from_guest[i]);
57 			bad = true;
58 		}
59 	}
60 
61 	if (bad)
62 		abort();
63 }
64 
test_sync_vmsa(uint32_t policy)65 static void test_sync_vmsa(uint32_t policy)
66 {
67 	struct kvm_vcpu *vcpu;
68 	struct kvm_vm *vm;
69 	vm_vaddr_t gva;
70 	void *hva;
71 
72 	double x87val = M_PI;
73 	struct kvm_xsave __attribute__((aligned(64))) xsave = { 0 };
74 
75 	vm = vm_sev_create_with_one_vcpu(KVM_X86_SEV_ES_VM, guest_code_xsave, &vcpu);
76 	gva = vm_vaddr_alloc_shared(vm, PAGE_SIZE, KVM_UTIL_MIN_VADDR,
77 				    MEM_REGION_TEST_DATA);
78 	hva = addr_gva2hva(vm, gva);
79 
80 	vcpu_args_set(vcpu, 1, gva);
81 
82 	asm("fninit\n"
83 	    "vpcmpeqb %%ymm4, %%ymm4, %%ymm4\n"
84 	    "fldl %3\n"
85 	    "xsave (%2)\n"
86 	    "fstp %%st\n"
87 	    : "=m"(xsave)
88 	    : "A"(XFEATURE_MASK_X87_AVX), "r"(&xsave), "m" (x87val)
89 	    : "ymm4", "st", "st(1)", "st(2)", "st(3)", "st(4)", "st(5)", "st(6)", "st(7)");
90 	vcpu_xsave_set(vcpu, &xsave);
91 
92 	vm_sev_launch(vm, SEV_POLICY_ES | policy, NULL);
93 
94 	/* This page is shared, so make it decrypted.  */
95 	memset(hva, 0, 4096);
96 
97 	vcpu_run(vcpu);
98 
99 	TEST_ASSERT(vcpu->run->exit_reason == KVM_EXIT_SYSTEM_EVENT,
100 		    "Wanted SYSTEM_EVENT, got %s",
101 		    exit_reason_str(vcpu->run->exit_reason));
102 	TEST_ASSERT_EQ(vcpu->run->system_event.type, KVM_SYSTEM_EVENT_SEV_TERM);
103 	TEST_ASSERT_EQ(vcpu->run->system_event.ndata, 1);
104 	TEST_ASSERT_EQ(vcpu->run->system_event.data[0], GHCB_MSR_TERM_REQ);
105 
106 	compare_xsave((u8 *)&xsave, (u8 *)hva);
107 
108 	kvm_vm_free(vm);
109 }
110 
test_sev(void * guest_code,uint64_t policy)111 static void test_sev(void *guest_code, uint64_t policy)
112 {
113 	struct kvm_vcpu *vcpu;
114 	struct kvm_vm *vm;
115 	struct ucall uc;
116 
117 	uint32_t type = policy & SEV_POLICY_ES ? KVM_X86_SEV_ES_VM : KVM_X86_SEV_VM;
118 
119 	vm = vm_sev_create_with_one_vcpu(type, guest_code, &vcpu);
120 
121 	/* TODO: Validate the measurement is as expected. */
122 	vm_sev_launch(vm, policy, NULL);
123 
124 	for (;;) {
125 		vcpu_run(vcpu);
126 
127 		if (policy & SEV_POLICY_ES) {
128 			TEST_ASSERT(vcpu->run->exit_reason == KVM_EXIT_SYSTEM_EVENT,
129 				    "Wanted SYSTEM_EVENT, got %s",
130 				    exit_reason_str(vcpu->run->exit_reason));
131 			TEST_ASSERT_EQ(vcpu->run->system_event.type, KVM_SYSTEM_EVENT_SEV_TERM);
132 			TEST_ASSERT_EQ(vcpu->run->system_event.ndata, 1);
133 			TEST_ASSERT_EQ(vcpu->run->system_event.data[0], GHCB_MSR_TERM_REQ);
134 			break;
135 		}
136 
137 		switch (get_ucall(vcpu, &uc)) {
138 		case UCALL_SYNC:
139 			continue;
140 		case UCALL_DONE:
141 			return;
142 		case UCALL_ABORT:
143 			REPORT_GUEST_ASSERT(uc);
144 		default:
145 			TEST_FAIL("Unexpected exit: %s",
146 				  exit_reason_str(vcpu->run->exit_reason));
147 		}
148 	}
149 
150 	kvm_vm_free(vm);
151 }
152 
guest_shutdown_code(void)153 static void guest_shutdown_code(void)
154 {
155 	struct desc_ptr idt;
156 
157 	/* Clobber the IDT so that #UD is guaranteed to trigger SHUTDOWN. */
158 	memset(&idt, 0, sizeof(idt));
159 	set_idt(&idt);
160 
161 	__asm__ __volatile__("ud2");
162 }
163 
test_sev_es_shutdown(void)164 static void test_sev_es_shutdown(void)
165 {
166 	struct kvm_vcpu *vcpu;
167 	struct kvm_vm *vm;
168 
169 	uint32_t type = KVM_X86_SEV_ES_VM;
170 
171 	vm = vm_sev_create_with_one_vcpu(type, guest_shutdown_code, &vcpu);
172 
173 	vm_sev_launch(vm, SEV_POLICY_ES, NULL);
174 
175 	vcpu_run(vcpu);
176 	TEST_ASSERT(vcpu->run->exit_reason == KVM_EXIT_SHUTDOWN,
177 		    "Wanted SHUTDOWN, got %s",
178 		    exit_reason_str(vcpu->run->exit_reason));
179 
180 	kvm_vm_free(vm);
181 }
182 
main(int argc,char * argv[])183 int main(int argc, char *argv[])
184 {
185 	const u64 xf_mask = XFEATURE_MASK_X87_AVX;
186 
187 	TEST_REQUIRE(kvm_cpu_has(X86_FEATURE_SEV));
188 
189 	test_sev(guest_sev_code, SEV_POLICY_NO_DBG);
190 	test_sev(guest_sev_code, 0);
191 
192 	if (kvm_cpu_has(X86_FEATURE_SEV_ES)) {
193 		test_sev(guest_sev_es_code, SEV_POLICY_ES | SEV_POLICY_NO_DBG);
194 		test_sev(guest_sev_es_code, SEV_POLICY_ES);
195 
196 		test_sev_es_shutdown();
197 
198 		if (kvm_has_cap(KVM_CAP_XCRS) &&
199 		    (xgetbv(0) & kvm_cpu_supported_xcr0() & xf_mask) == xf_mask) {
200 			test_sync_vmsa(0);
201 			test_sync_vmsa(SEV_POLICY_NO_DBG);
202 		}
203 	}
204 
205 	return 0;
206 }
207