linux/tools/testing/selftests/kvm/x86_64/triple_fault_event_test.c

// SPDX-License-Identifier: GPL-2.0-only
#include "test_util.h"
#include "kvm_util.h"
#include "processor.h"
#include "vmx.h"
#include "svm_util.h"

#include <string.h>
#include <sys/ioctl.h>

#include "kselftest.h"

#define ARBITRARY_IO_PORT	0x2000

/* The virtual machine object. */
static struct kvm_vm *vm;

static void l2_guest_code(void)
{
	asm volatile("inb %%dx, %%al"
		     : : [port] "d" (ARBITRARY_IO_PORT) : "rax");
}

#define L2_GUEST_STACK_SIZE 64
unsigned long l2_guest_stack[L2_GUEST_STACK_SIZE];

void l1_guest_code_vmx(struct vmx_pages *vmx)
{

	GUEST_ASSERT(vmx->vmcs_gpa);
	GUEST_ASSERT(prepare_for_vmx_operation(vmx));
	GUEST_ASSERT(load_vmcs(vmx));

	prepare_vmcs(vmx, l2_guest_code,
		     &l2_guest_stack[L2_GUEST_STACK_SIZE]);

	GUEST_ASSERT(!vmlaunch());
	/* L2 should triple fault after a triple fault event injected. */
	GUEST_ASSERT(vmreadz(VM_EXIT_REASON) == EXIT_REASON_TRIPLE_FAULT);
	GUEST_DONE();
}

void l1_guest_code_svm(struct svm_test_data *svm)
{
	struct vmcb *vmcb = svm->vmcb;

	generic_svm_setup(svm, l2_guest_code,
			&l2_guest_stack[L2_GUEST_STACK_SIZE]);

	/* don't intercept shutdown to test the case of SVM allowing to do so */
	vmcb->control.intercept &= ~(BIT(INTERCEPT_SHUTDOWN));

	run_guest(vmcb, svm->vmcb_gpa);

	/* should not reach here, L1 should crash  */
	GUEST_ASSERT(0);
}

int main(void)
{
	struct kvm_vcpu *vcpu;
	struct kvm_run *run;
	struct kvm_vcpu_events events;
	struct ucall uc;

	bool has_vmx = kvm_cpu_has(X86_FEATURE_VMX);
	bool has_svm = kvm_cpu_has(X86_FEATURE_SVM);

	TEST_REQUIRE(has_vmx || has_svm);

	TEST_REQUIRE(kvm_has_cap(KVM_CAP_X86_TRIPLE_FAULT_EVENT));


	if (has_vmx) {
		vm_vaddr_t vmx_pages_gva;

		vm = vm_create_with_one_vcpu(&vcpu, l1_guest_code_vmx);
		vcpu_alloc_vmx(vm, &vmx_pages_gva);
		vcpu_args_set(vcpu, 1, vmx_pages_gva);
	} else {
		vm_vaddr_t svm_gva;

		vm = vm_create_with_one_vcpu(&vcpu, l1_guest_code_svm);
		vcpu_alloc_svm(vm, &svm_gva);
		vcpu_args_set(vcpu, 1, svm_gva);
	}

	vm_enable_cap(vm, KVM_CAP_X86_TRIPLE_FAULT_EVENT, 1);
	run = vcpu->run;
	vcpu_run(vcpu);

	TEST_ASSERT_KVM_EXIT_REASON(vcpu, KVM_EXIT_IO);
	TEST_ASSERT(run->io.port == ARBITRARY_IO_PORT,
		    "Expected IN from port %d from L2, got port %d",
		    ARBITRARY_IO_PORT, run->io.port);
	vcpu_events_get(vcpu, &events);
	events.flags |= KVM_VCPUEVENT_VALID_TRIPLE_FAULT;
	events.triple_fault.pending = true;
	vcpu_events_set(vcpu, &events);
	run->immediate_exit = true;
	vcpu_run_complete_io(vcpu);

	vcpu_events_get(vcpu, &events);
	TEST_ASSERT(events.flags & KVM_VCPUEVENT_VALID_TRIPLE_FAULT,
		    "Triple fault event invalid");
	TEST_ASSERT(events.triple_fault.pending,
		    "No triple fault pending");
	vcpu_run(vcpu);


	if (has_svm) {
		TEST_ASSERT_KVM_EXIT_REASON(vcpu, KVM_EXIT_SHUTDOWN);
	} else {
		switch (get_ucall(vcpu, &uc)) {
		case UCALL_DONE:
			break;
		case UCALL_ABORT:
			REPORT_GUEST_ASSERT(uc);
		default:
			TEST_FAIL("Unexpected ucall: %lu", uc.cmd);
		}
	}
	return 0;
}