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 1// SPDX-License-Identifier: GPL-2.0-only
 2/*
 3 * Test Hyper-V extended hypercall, HV_EXT_CALL_QUERY_CAPABILITIES (0x8001),
 4 * exit to userspace and receive result in guest.
 5 *
 6 * Negative tests are present in hyperv_features.c
 7 *
 8 * Copyright 2022 Google LLC
 9 * Author: Vipin Sharma <vipinsh@google.com>
10 */
11#include "kvm_util.h"
12#include "processor.h"
13#include "hyperv.h"
14
15/* Any value is fine */
16#define EXT_CAPABILITIES 0xbull
17
18static void guest_code(vm_paddr_t in_pg_gpa, vm_paddr_t out_pg_gpa,
19		       vm_vaddr_t out_pg_gva)
20{
21	uint64_t *output_gva;
22
23	wrmsr(HV_X64_MSR_GUEST_OS_ID, HYPERV_LINUX_OS_ID);
24	wrmsr(HV_X64_MSR_HYPERCALL, in_pg_gpa);
25
26	output_gva = (uint64_t *)out_pg_gva;
27
28	hyperv_hypercall(HV_EXT_CALL_QUERY_CAPABILITIES, in_pg_gpa, out_pg_gpa);
29
30	/* TLFS states output will be a uint64_t value */
31	GUEST_ASSERT_EQ(*output_gva, EXT_CAPABILITIES);
32
33	GUEST_DONE();
34}
35
36int main(void)
37{
38	vm_vaddr_t hcall_out_page;
39	vm_vaddr_t hcall_in_page;
40	struct kvm_vcpu *vcpu;
41	struct kvm_run *run;
42	struct kvm_vm *vm;
43	uint64_t *outval;
44	struct ucall uc;
45
46	TEST_REQUIRE(kvm_has_cap(KVM_CAP_HYPERV_CPUID));
47
48	/* Verify if extended hypercalls are supported */
49	if (!kvm_cpuid_has(kvm_get_supported_hv_cpuid(),
50			   HV_ENABLE_EXTENDED_HYPERCALLS)) {
51		print_skip("Extended calls not supported by the kernel");
52		exit(KSFT_SKIP);
53	}
54
55	vm = vm_create_with_one_vcpu(&vcpu, guest_code);
56	run = vcpu->run;
57	vcpu_set_hv_cpuid(vcpu);
58
59	/* Hypercall input */
60	hcall_in_page = vm_vaddr_alloc_pages(vm, 1);
61	memset(addr_gva2hva(vm, hcall_in_page), 0x0, vm->page_size);
62
63	/* Hypercall output */
64	hcall_out_page = vm_vaddr_alloc_pages(vm, 1);
65	memset(addr_gva2hva(vm, hcall_out_page), 0x0, vm->page_size);
66
67	vcpu_args_set(vcpu, 3, addr_gva2gpa(vm, hcall_in_page),
68		      addr_gva2gpa(vm, hcall_out_page), hcall_out_page);
69
70	vcpu_run(vcpu);
71
72	TEST_ASSERT(run->exit_reason == KVM_EXIT_HYPERV,
73		    "Unexpected exit reason: %u (%s)",
74		    run->exit_reason, exit_reason_str(run->exit_reason));
75
76	outval = addr_gpa2hva(vm, run->hyperv.u.hcall.params[1]);
77	*outval = EXT_CAPABILITIES;
78	run->hyperv.u.hcall.result = HV_STATUS_SUCCESS;
79
80	vcpu_run(vcpu);
81
82	TEST_ASSERT(run->exit_reason == KVM_EXIT_IO,
83		    "Unexpected exit reason: %u (%s)",
84		    run->exit_reason, exit_reason_str(run->exit_reason));
85
86	switch (get_ucall(vcpu, &uc)) {
87	case UCALL_ABORT:
88		REPORT_GUEST_ASSERT(uc);
89		break;
90	case UCALL_DONE:
91		break;
92	default:
93		TEST_FAIL("Unhandled ucall: %ld", uc.cmd);
94	}
95
96	kvm_vm_free(vm);
97	return 0;
98}
1