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