xref: /linux/tools/testing/selftests/kvm/x86_64/sev_smoke_test.c (revision 46e6acfe3501fa938af9c5bd730f0020235b08a2)
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 
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 
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 $-1, %eax\n"
45     "mov $-1, %edx\n"
46     "xsave (%rdi)\n"
47     "jmp guest_sev_es_code");
48 
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 %02hhx | %02hhx %02hhx\n", i, from_host[i], from_guest[i]);
56 			bad = true;
57 		}
58 	}
59 
60 	if (bad)
61 		abort();
62 }
63 
64 static void test_sync_vmsa(uint32_t policy)
65 {
66 	struct kvm_vcpu *vcpu;
67 	struct kvm_vm *vm;
68 	vm_vaddr_t gva;
69 	void *hva;
70 
71 	double x87val = M_PI;
72 	struct kvm_xsave __attribute__((aligned(64))) xsave = { 0 };
73 	struct kvm_sregs sregs;
74 	struct kvm_xcrs xcrs = {
75 		.nr_xcrs = 1,
76 		.xcrs[0].xcr = 0,
77 		.xcrs[0].value = XFEATURE_MASK_X87_AVX,
78 	};
79 
80 	vm = vm_sev_create_with_one_vcpu(KVM_X86_SEV_ES_VM, guest_code_xsave, &vcpu);
81 	gva = vm_vaddr_alloc_shared(vm, PAGE_SIZE, KVM_UTIL_MIN_VADDR,
82 				    MEM_REGION_TEST_DATA);
83 	hva = addr_gva2hva(vm, gva);
84 
85 	vcpu_args_set(vcpu, 1, gva);
86 
87 	vcpu_sregs_get(vcpu, &sregs);
88 	sregs.cr4 |= X86_CR4_OSFXSR | X86_CR4_OSXSAVE;
89 	vcpu_sregs_set(vcpu, &sregs);
90 
91 	vcpu_xcrs_set(vcpu, &xcrs);
92 	asm("fninit\n"
93 	    "vpcmpeqb %%ymm4, %%ymm4, %%ymm4\n"
94 	    "fldl %3\n"
95 	    "xsave (%2)\n"
96 	    "fstp %%st\n"
97 	    : "=m"(xsave)
98 	    : "A"(XFEATURE_MASK_X87_AVX), "r"(&xsave), "m" (x87val)
99 	    : "ymm4", "st", "st(1)", "st(2)", "st(3)", "st(4)", "st(5)", "st(6)", "st(7)");
100 	vcpu_xsave_set(vcpu, &xsave);
101 
102 	vm_sev_launch(vm, SEV_POLICY_ES | policy, NULL);
103 
104 	/* This page is shared, so make it decrypted.  */
105 	memset(hva, 0, 4096);
106 
107 	vcpu_run(vcpu);
108 
109 	TEST_ASSERT(vcpu->run->exit_reason == KVM_EXIT_SYSTEM_EVENT,
110 		    "Wanted SYSTEM_EVENT, got %s",
111 		    exit_reason_str(vcpu->run->exit_reason));
112 	TEST_ASSERT_EQ(vcpu->run->system_event.type, KVM_SYSTEM_EVENT_SEV_TERM);
113 	TEST_ASSERT_EQ(vcpu->run->system_event.ndata, 1);
114 	TEST_ASSERT_EQ(vcpu->run->system_event.data[0], GHCB_MSR_TERM_REQ);
115 
116 	compare_xsave((u8 *)&xsave, (u8 *)hva);
117 
118 	kvm_vm_free(vm);
119 }
120 
121 static void test_sev(void *guest_code, uint64_t policy)
122 {
123 	struct kvm_vcpu *vcpu;
124 	struct kvm_vm *vm;
125 	struct ucall uc;
126 
127 	uint32_t type = policy & SEV_POLICY_ES ? KVM_X86_SEV_ES_VM : KVM_X86_SEV_VM;
128 
129 	vm = vm_sev_create_with_one_vcpu(type, guest_code, &vcpu);
130 
131 	/* TODO: Validate the measurement is as expected. */
132 	vm_sev_launch(vm, policy, NULL);
133 
134 	for (;;) {
135 		vcpu_run(vcpu);
136 
137 		if (policy & SEV_POLICY_ES) {
138 			TEST_ASSERT(vcpu->run->exit_reason == KVM_EXIT_SYSTEM_EVENT,
139 				    "Wanted SYSTEM_EVENT, got %s",
140 				    exit_reason_str(vcpu->run->exit_reason));
141 			TEST_ASSERT_EQ(vcpu->run->system_event.type, KVM_SYSTEM_EVENT_SEV_TERM);
142 			TEST_ASSERT_EQ(vcpu->run->system_event.ndata, 1);
143 			TEST_ASSERT_EQ(vcpu->run->system_event.data[0], GHCB_MSR_TERM_REQ);
144 			break;
145 		}
146 
147 		switch (get_ucall(vcpu, &uc)) {
148 		case UCALL_SYNC:
149 			continue;
150 		case UCALL_DONE:
151 			return;
152 		case UCALL_ABORT:
153 			REPORT_GUEST_ASSERT(uc);
154 		default:
155 			TEST_FAIL("Unexpected exit: %s",
156 				  exit_reason_str(vcpu->run->exit_reason));
157 		}
158 	}
159 
160 	kvm_vm_free(vm);
161 }
162 
163 int main(int argc, char *argv[])
164 {
165 	TEST_REQUIRE(kvm_cpu_has(X86_FEATURE_SEV));
166 
167 	test_sev(guest_sev_code, SEV_POLICY_NO_DBG);
168 	test_sev(guest_sev_code, 0);
169 
170 	if (kvm_cpu_has(X86_FEATURE_SEV_ES)) {
171 		test_sev(guest_sev_es_code, SEV_POLICY_ES | SEV_POLICY_NO_DBG);
172 		test_sev(guest_sev_es_code, SEV_POLICY_ES);
173 
174 		if (kvm_has_cap(KVM_CAP_XCRS) &&
175 		    (xgetbv(0) & XFEATURE_MASK_X87_AVX) == XFEATURE_MASK_X87_AVX) {
176 			test_sync_vmsa(0);
177 			test_sync_vmsa(SEV_POLICY_NO_DBG);
178 		}
179 	}
180 
181 	return 0;
182 }
183