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 #define VCPU_ID		0
17 
18 static struct kvm_vm *vm;
19 
20 bool vintr_irq_called;
21 bool intr_irq_called;
22 
23 #define VINTR_IRQ_NUMBER 0x20
24 #define INTR_IRQ_NUMBER 0x30
25 
26 static void vintr_irq_handler(struct ex_regs *regs)
27 {
28 	vintr_irq_called = true;
29 }
30 
31 static void intr_irq_handler(struct ex_regs *regs)
32 {
33 	x2apic_write_reg(APIC_EOI, 0x00);
34 	intr_irq_called = true;
35 }
36 
37 static void l2_guest_code(struct svm_test_data *svm)
38 {
39 	/* This code raises interrupt INTR_IRQ_NUMBER in the L1's LAPIC,
40 	 * and since L1 didn't enable virtual interrupt masking,
41 	 * L2 should receive it and not L1.
42 	 *
43 	 * L2 also has virtual interrupt 'VINTR_IRQ_NUMBER' pending in V_IRQ
44 	 * so it should also receive it after the following 'sti'.
45 	 */
46 	x2apic_write_reg(APIC_ICR,
47 		APIC_DEST_SELF | APIC_INT_ASSERT | INTR_IRQ_NUMBER);
48 
49 	__asm__ __volatile__(
50 		"sti\n"
51 		"nop\n"
52 	);
53 
54 	GUEST_ASSERT(vintr_irq_called);
55 	GUEST_ASSERT(intr_irq_called);
56 
57 	__asm__ __volatile__(
58 		"vmcall\n"
59 	);
60 }
61 
62 static void l1_guest_code(struct svm_test_data *svm)
63 {
64 	#define L2_GUEST_STACK_SIZE 64
65 	unsigned long l2_guest_stack[L2_GUEST_STACK_SIZE];
66 	struct vmcb *vmcb = svm->vmcb;
67 
68 	x2apic_enable();
69 
70 	/* Prepare for L2 execution. */
71 	generic_svm_setup(svm, l2_guest_code,
72 			  &l2_guest_stack[L2_GUEST_STACK_SIZE]);
73 
74 	/* No virtual interrupt masking */
75 	vmcb->control.int_ctl &= ~V_INTR_MASKING_MASK;
76 
77 	/* No intercepts for real and virtual interrupts */
78 	vmcb->control.intercept &= ~(BIT(INTERCEPT_INTR) | BIT(INTERCEPT_VINTR));
79 
80 	/* Make a virtual interrupt VINTR_IRQ_NUMBER pending */
81 	vmcb->control.int_ctl |= V_IRQ_MASK | (0x1 << V_INTR_PRIO_SHIFT);
82 	vmcb->control.int_vector = VINTR_IRQ_NUMBER;
83 
84 	run_guest(vmcb, svm->vmcb_gpa);
85 	GUEST_ASSERT(vmcb->control.exit_code == SVM_EXIT_VMMCALL);
86 	GUEST_DONE();
87 }
88 
89 int main(int argc, char *argv[])
90 {
91 	vm_vaddr_t svm_gva;
92 
93 	nested_svm_check_supported();
94 
95 	vm = vm_create_default(VCPU_ID, 0, (void *) l1_guest_code);
96 
97 	vm_init_descriptor_tables(vm);
98 	vcpu_init_descriptor_tables(vm, VCPU_ID);
99 
100 	vm_install_exception_handler(vm, VINTR_IRQ_NUMBER, vintr_irq_handler);
101 	vm_install_exception_handler(vm, INTR_IRQ_NUMBER, intr_irq_handler);
102 
103 	vcpu_alloc_svm(vm, &svm_gva);
104 	vcpu_args_set(vm, VCPU_ID, 1, svm_gva);
105 
106 	struct kvm_run *run = vcpu_state(vm, VCPU_ID);
107 	struct ucall uc;
108 
109 	vcpu_run(vm, VCPU_ID);
110 	TEST_ASSERT(run->exit_reason == KVM_EXIT_IO,
111 		    "Got exit_reason other than KVM_EXIT_IO: %u (%s)\n",
112 		    run->exit_reason,
113 		    exit_reason_str(run->exit_reason));
114 
115 	switch (get_ucall(vm, VCPU_ID, &uc)) {
116 	case UCALL_ABORT:
117 		TEST_FAIL("%s", (const char *)uc.args[0]);
118 		break;
119 		/* NOT REACHED */
120 	case UCALL_DONE:
121 		goto done;
122 	default:
123 		TEST_FAIL("Unknown ucall 0x%lx.", uc.cmd);
124 	}
125 done:
126 	kvm_vm_free(vm);
127 	return 0;
128 }
129