KVM: selftests: x86: Use TAP interface in the fix_hypercall test

Use the kvm_test_harness.h interface in this test to get TAP
output, so that it is easier for the user to see what the test
is doing.
Signed-off-by: Thomas Huth <thuth@redhat.com>
Link: https://lore.kernel.org/r/20240208204844.119326-7-thuth@redhat.comSigned-off-by: Sean Christopherson <seanjc@google.com>

tools/testing/selftests/kvm/x86_64/fix_hypercall_test.c

@@ -9,6 +9,7 @@
 #include <linux/stringify.h>
 #include <stdint.h>
 
+#include "kvm_test_harness.h"
 #include "apic.h"
 #include "test_util.h"
 #include "kvm_util.h"
@@ -83,6 +84,8 @@ static void guest_main(void)
 	GUEST_DONE();
 }
 
+KVM_ONE_VCPU_TEST_SUITE(fix_hypercall);
+
 static void enter_guest(struct kvm_vcpu *vcpu)
 {
 	struct kvm_run *run = vcpu->run;
@@ -103,14 +106,11 @@ static void enter_guest(struct kvm_vcpu *vcpu)
 	}
 }
 
-static void test_fix_hypercall(bool disable_quirk)
+static void test_fix_hypercall(struct kvm_vcpu *vcpu, bool disable_quirk)
 {
-	struct kvm_vcpu *vcpu;
-	struct kvm_vm *vm;
-
-	vm = vm_create_with_one_vcpu(&vcpu, guest_main);
+	struct kvm_vm *vm = vcpu->vm;
 
-	vm_init_descriptor_tables(vcpu->vm);
+	vm_init_descriptor_tables(vm);
 	vcpu_init_descriptor_tables(vcpu);
 	vm_install_exception_handler(vcpu->vm, UD_VECTOR, guest_ud_handler);
 
@@ -126,10 +126,19 @@ static void test_fix_hypercall(bool disable_quirk)
 	enter_guest(vcpu);
 }
 
-int main(void)
+KVM_ONE_VCPU_TEST(fix_hypercall, enable_quirk, guest_main)
+{
+	test_fix_hypercall(vcpu, false);
+}
+
+KVM_ONE_VCPU_TEST(fix_hypercall, disable_quirk, guest_main)
+{
+	test_fix_hypercall(vcpu, true);
+}
+
+int main(int argc, char *argv[])
 {
 	TEST_REQUIRE(kvm_check_cap(KVM_CAP_DISABLE_QUIRKS2) & KVM_X86_QUIRK_FIX_HYPERCALL_INSN);
 
-	test_fix_hypercall(false);
-	test_fix_hypercall(true);
+	return test_harness_run(argc, argv);
 }