1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * svm_int_ctl_test
4  *
5  * Copyright (C) 2021, Red Hat, Inc.
6  *
7  * Nested SVM testing: test simultaneous use of V_IRQ from L1 and L0.
8  */
9 
10 #include "test_util.h"
11 #include "kvm_util.h"
12 #include "processor.h"
13 #include "svm_util.h"
14 #include "apic.h"
15 
16 bool vintr_irq_called;
17 bool intr_irq_called;
18 
19 #define VINTR_IRQ_NUMBER 0x20
20 #define INTR_IRQ_NUMBER 0x30
21 
22 static void vintr_irq_handler(struct ex_regs *regs)
23 {
24 	vintr_irq_called = true;
25 }
26 
27 static void intr_irq_handler(struct ex_regs *regs)
28 {
29 	x2apic_write_reg(APIC_EOI, 0x00);
30 	intr_irq_called = true;
31 }
32 
33 static void l2_guest_code(struct svm_test_data *svm)
34 {
35 	/* This code raises interrupt INTR_IRQ_NUMBER in the L1's LAPIC,
36 	 * and since L1 didn't enable virtual interrupt masking,
37 	 * L2 should receive it and not L1.
38 	 *
39 	 * L2 also has virtual interrupt 'VINTR_IRQ_NUMBER' pending in V_IRQ
40 	 * so it should also receive it after the following 'sti'.
41 	 */
42 	x2apic_write_reg(APIC_ICR,
43 		APIC_DEST_SELF | APIC_INT_ASSERT | INTR_IRQ_NUMBER);
44 
45 	__asm__ __volatile__(
46 		"sti\n"
47 		"nop\n"
48 	);
49 
50 	GUEST_ASSERT(vintr_irq_called);
51 	GUEST_ASSERT(intr_irq_called);
52 
53 	__asm__ __volatile__(
54 		"vmcall\n"
55 	);
56 }
57 
58 static void l1_guest_code(struct svm_test_data *svm)
59 {
60 	#define L2_GUEST_STACK_SIZE 64
61 	unsigned long l2_guest_stack[L2_GUEST_STACK_SIZE];
62 	struct vmcb *vmcb = svm->vmcb;
63 
64 	x2apic_enable();
65 
66 	/* Prepare for L2 execution. */
67 	generic_svm_setup(svm, l2_guest_code,
68 			  &l2_guest_stack[L2_GUEST_STACK_SIZE]);
69 
70 	/* No virtual interrupt masking */
71 	vmcb->control.int_ctl &= ~V_INTR_MASKING_MASK;
72 
73 	/* No intercepts for real and virtual interrupts */
74 	vmcb->control.intercept &= ~(BIT(INTERCEPT_INTR) | BIT(INTERCEPT_VINTR));
75 
76 	/* Make a virtual interrupt VINTR_IRQ_NUMBER pending */
77 	vmcb->control.int_ctl |= V_IRQ_MASK | (0x1 << V_INTR_PRIO_SHIFT);
78 	vmcb->control.int_vector = VINTR_IRQ_NUMBER;
79 
80 	run_guest(vmcb, svm->vmcb_gpa);
81 	GUEST_ASSERT(vmcb->control.exit_code == SVM_EXIT_VMMCALL);
82 	GUEST_DONE();
83 }
84 
85 int main(int argc, char *argv[])
86 {
87 	struct kvm_vcpu *vcpu;
88 	vm_vaddr_t svm_gva;
89 	struct kvm_vm *vm;
90 	struct ucall uc;
91 
92 	TEST_REQUIRE(kvm_cpu_has(X86_FEATURE_SVM));
93 
94 	vm = vm_create_with_one_vcpu(&vcpu, l1_guest_code);
95 
96 	vm_init_descriptor_tables(vm);
97 	vcpu_init_descriptor_tables(vcpu);
98 
99 	vm_install_exception_handler(vm, VINTR_IRQ_NUMBER, vintr_irq_handler);
100 	vm_install_exception_handler(vm, INTR_IRQ_NUMBER, intr_irq_handler);
101 
102 	vcpu_alloc_svm(vm, &svm_gva);
103 	vcpu_args_set(vcpu, 1, svm_gva);
104 
105 	vcpu_run(vcpu);
106 	TEST_ASSERT_KVM_EXIT_REASON(vcpu, KVM_EXIT_IO);
107 
108 	switch (get_ucall(vcpu, &uc)) {
109 	case UCALL_ABORT:
110 		REPORT_GUEST_ASSERT(uc);
111 		break;
112 		/* NOT REACHED */
113 	case UCALL_DONE:
114 		goto done;
115 	default:
116 		TEST_FAIL("Unknown ucall 0x%lx.", uc.cmd);
117 	}
118 done:
119 	kvm_vm_free(vm);
120 	return 0;
121 }
122