xref: /linux/tools/testing/selftests/kvm/x86/nested_close_kvm_test.c (revision 509d3f45847627f4c5cdce004c3ec79262b5239c)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2019, Red Hat, Inc.
4  *
5  * Verify that nothing bad happens if a KVM user exits with open
6  * file descriptors while executing a nested guest.
7  */
8 
9 #include "test_util.h"
10 #include "kvm_util.h"
11 #include "processor.h"
12 #include "vmx.h"
13 #include "svm_util.h"
14 
15 #include <string.h>
16 #include <sys/ioctl.h>
17 
18 #include "kselftest.h"
19 
20 enum {
21 	PORT_L0_EXIT = 0x2000,
22 };
23 
24 #define L2_GUEST_STACK_SIZE 64
25 
26 static void l2_guest_code(void)
27 {
28 	/* Exit to L0 */
29 	asm volatile("inb %%dx, %%al"
30 		     : : [port] "d" (PORT_L0_EXIT) : "rax");
31 }
32 
33 static void l1_vmx_code(struct vmx_pages *vmx_pages)
34 {
35 	unsigned long l2_guest_stack[L2_GUEST_STACK_SIZE];
36 
37 	GUEST_ASSERT(prepare_for_vmx_operation(vmx_pages));
38 	GUEST_ASSERT(load_vmcs(vmx_pages));
39 
40 	/* Prepare the VMCS for L2 execution. */
41 	prepare_vmcs(vmx_pages, l2_guest_code,
42 		     &l2_guest_stack[L2_GUEST_STACK_SIZE]);
43 
44 	GUEST_ASSERT(!vmlaunch());
45 	GUEST_ASSERT(0);
46 }
47 
48 static void l1_svm_code(struct svm_test_data *svm)
49 {
50 	unsigned long l2_guest_stack[L2_GUEST_STACK_SIZE];
51 
52 	/* Prepare the VMCB for L2 execution. */
53 	generic_svm_setup(svm, l2_guest_code,
54 			  &l2_guest_stack[L2_GUEST_STACK_SIZE]);
55 
56 	run_guest(svm->vmcb, svm->vmcb_gpa);
57 	GUEST_ASSERT(0);
58 }
59 
60 static void l1_guest_code(void *data)
61 {
62 	if (this_cpu_has(X86_FEATURE_VMX))
63 		l1_vmx_code(data);
64 	else
65 		l1_svm_code(data);
66 }
67 
68 int main(int argc, char *argv[])
69 {
70 	vm_vaddr_t guest_gva;
71 	struct kvm_vcpu *vcpu;
72 	struct kvm_vm *vm;
73 
74 	TEST_REQUIRE(kvm_cpu_has(X86_FEATURE_VMX) ||
75 		     kvm_cpu_has(X86_FEATURE_SVM));
76 
77 	vm = vm_create_with_one_vcpu(&vcpu, l1_guest_code);
78 
79 	if (kvm_cpu_has(X86_FEATURE_VMX))
80 		vcpu_alloc_vmx(vm, &guest_gva);
81 	else
82 		vcpu_alloc_svm(vm, &guest_gva);
83 
84 	vcpu_args_set(vcpu, 1, guest_gva);
85 
86 	for (;;) {
87 		volatile struct kvm_run *run = vcpu->run;
88 		struct ucall uc;
89 
90 		vcpu_run(vcpu);
91 		TEST_ASSERT_KVM_EXIT_REASON(vcpu, KVM_EXIT_IO);
92 
93 		if (run->io.port == PORT_L0_EXIT)
94 			break;
95 
96 		switch (get_ucall(vcpu, &uc)) {
97 		case UCALL_ABORT:
98 			REPORT_GUEST_ASSERT(uc);
99 			/* NOT REACHED */
100 		default:
101 			TEST_FAIL("Unknown ucall %lu", uc.cmd);
102 		}
103 	}
104 }
105