1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * xen_vmcall_test
4 *
5 * Copyright © 2020 Amazon.com, Inc. or its affiliates.
6 *
7 * Userspace hypercall testing
8 */
9
10 #include "test_util.h"
11 #include "kvm_util.h"
12 #include "processor.h"
13 #include "hyperv.h"
14
15 #define HCALL_REGION_GPA 0xc0000000ULL
16 #define HCALL_REGION_SLOT 10
17
18 #define INPUTVALUE 17
19 #define ARGVALUE(x) (0xdeadbeef5a5a0000UL + x)
20 #define RETVALUE 0xcafef00dfbfbffffUL
21
22 #define XEN_HYPERCALL_MSR 0x40000200
23 #define HV_GUEST_OS_ID_MSR 0x40000000
24 #define HV_HYPERCALL_MSR 0x40000001
25
26 #define HVCALL_SIGNAL_EVENT 0x005d
27 #define HV_STATUS_INVALID_ALIGNMENT 4
28
guest_code(void)29 static void guest_code(void)
30 {
31 unsigned long rax = INPUTVALUE;
32 unsigned long rdi = ARGVALUE(1);
33 unsigned long rsi = ARGVALUE(2);
34 unsigned long rdx = ARGVALUE(3);
35 unsigned long rcx;
36 register unsigned long r10 __asm__("r10") = ARGVALUE(4);
37 register unsigned long r8 __asm__("r8") = ARGVALUE(5);
38 register unsigned long r9 __asm__("r9") = ARGVALUE(6);
39
40 /* First a direct invocation of 'vmcall' */
41 __asm__ __volatile__("vmcall" :
42 "=a"(rax) :
43 "a"(rax), "D"(rdi), "S"(rsi), "d"(rdx),
44 "r"(r10), "r"(r8), "r"(r9));
45 GUEST_ASSERT(rax == RETVALUE);
46
47 /* Fill in the Xen hypercall page */
48 __asm__ __volatile__("wrmsr" : : "c" (XEN_HYPERCALL_MSR),
49 "a" (HCALL_REGION_GPA & 0xffffffff),
50 "d" (HCALL_REGION_GPA >> 32));
51
52 /* Set Hyper-V Guest OS ID */
53 __asm__ __volatile__("wrmsr" : : "c" (HV_GUEST_OS_ID_MSR),
54 "a" (0x5a), "d" (0));
55
56 /* Hyper-V hypercall page */
57 u64 msrval = HCALL_REGION_GPA + PAGE_SIZE + 1;
58 __asm__ __volatile__("wrmsr" : : "c" (HV_HYPERCALL_MSR),
59 "a" (msrval & 0xffffffff),
60 "d" (msrval >> 32));
61
62 /* Invoke a Xen hypercall */
63 __asm__ __volatile__("call *%1" : "=a"(rax) :
64 "r"(HCALL_REGION_GPA + INPUTVALUE * 32),
65 "a"(rax), "D"(rdi), "S"(rsi), "d"(rdx),
66 "r"(r10), "r"(r8), "r"(r9));
67 GUEST_ASSERT(rax == RETVALUE);
68
69 /* Invoke a Hyper-V hypercall */
70 rax = 0;
71 rcx = HVCALL_SIGNAL_EVENT; /* code */
72 rdx = 0x5a5a5a5a; /* ingpa (badly aligned) */
73 __asm__ __volatile__("call *%1" : "=a"(rax) :
74 "r"(HCALL_REGION_GPA + PAGE_SIZE),
75 "a"(rax), "c"(rcx), "d"(rdx),
76 "r"(r8));
77 GUEST_ASSERT(rax == HV_STATUS_INVALID_ALIGNMENT);
78
79 GUEST_DONE();
80 }
81
main(int argc,char * argv[])82 int main(int argc, char *argv[])
83 {
84 unsigned int xen_caps;
85 struct kvm_vcpu *vcpu;
86 struct kvm_vm *vm;
87
88 xen_caps = kvm_check_cap(KVM_CAP_XEN_HVM);
89 TEST_REQUIRE(xen_caps & KVM_XEN_HVM_CONFIG_INTERCEPT_HCALL);
90
91 vm = vm_create_with_one_vcpu(&vcpu, guest_code);
92 vcpu_set_hv_cpuid(vcpu);
93
94 struct kvm_xen_hvm_config hvmc = {
95 .flags = KVM_XEN_HVM_CONFIG_INTERCEPT_HCALL,
96 .msr = XEN_HYPERCALL_MSR,
97 };
98 vm_ioctl(vm, KVM_XEN_HVM_CONFIG, &hvmc);
99
100 /* Map a region for the hypercall pages */
101 vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS,
102 HCALL_REGION_GPA, HCALL_REGION_SLOT, 2, 0);
103 virt_map(vm, HCALL_REGION_GPA, HCALL_REGION_GPA, 2);
104
105 for (;;) {
106 volatile struct kvm_run *run = vcpu->run;
107 struct ucall uc;
108
109 vcpu_run(vcpu);
110
111 if (run->exit_reason == KVM_EXIT_XEN) {
112 TEST_ASSERT_EQ(run->xen.type, KVM_EXIT_XEN_HCALL);
113 TEST_ASSERT_EQ(run->xen.u.hcall.cpl, 0);
114 TEST_ASSERT_EQ(run->xen.u.hcall.longmode, 1);
115 TEST_ASSERT_EQ(run->xen.u.hcall.input, INPUTVALUE);
116 TEST_ASSERT_EQ(run->xen.u.hcall.params[0], ARGVALUE(1));
117 TEST_ASSERT_EQ(run->xen.u.hcall.params[1], ARGVALUE(2));
118 TEST_ASSERT_EQ(run->xen.u.hcall.params[2], ARGVALUE(3));
119 TEST_ASSERT_EQ(run->xen.u.hcall.params[3], ARGVALUE(4));
120 TEST_ASSERT_EQ(run->xen.u.hcall.params[4], ARGVALUE(5));
121 TEST_ASSERT_EQ(run->xen.u.hcall.params[5], ARGVALUE(6));
122 run->xen.u.hcall.result = RETVALUE;
123 continue;
124 }
125
126 TEST_ASSERT_KVM_EXIT_REASON(vcpu, KVM_EXIT_IO);
127
128 switch (get_ucall(vcpu, &uc)) {
129 case UCALL_ABORT:
130 REPORT_GUEST_ASSERT(uc);
131 /* NOT REACHED */
132 case UCALL_SYNC:
133 break;
134 case UCALL_DONE:
135 goto done;
136 default:
137 TEST_FAIL("Unknown ucall 0x%lx.", uc.cmd);
138 }
139 }
140 done:
141 kvm_vm_free(vm);
142 return 0;
143 }
144