KVM: selftests: Dedup subtests of fix_hypercall_test

Combine fix_hypercall_test's two subtests into a common routine, the only
difference between the two is whether or not the quirk is disabled.
Passing a boolean is a little gross, but using an enum to make it super
obvious that the callers are enabling/disabling the quirk seems like
overkill.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Message-Id: <20220928233652.783504-7-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

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

@@ -17,7 +17,7 @@
 /* VMCALL and VMMCALL are both 3-byte opcodes. */
 #define HYPERCALL_INSN_SIZE	3
 
-static bool ud_expected;
+static bool quirk_disabled;
 
 static void guest_ud_handler(struct ex_regs *regs)
 {
@@ -70,7 +70,7 @@ static void guest_main(void)
 	 * enabled, verify that the hypercall succeeded and that KVM patched in
 	 * the "right" hypercall.
 	 */
-	if (ud_expected) {
+	if (quirk_disabled) {
 		GUEST_ASSERT(ret == (uint64_t)-EFAULT);
 		GUEST_ASSERT(!memcmp(other_hypercall_insn, hypercall_insn,
 			     HYPERCALL_INSN_SIZE));
@@ -83,13 +83,6 @@ static void guest_main(void)
 	GUEST_DONE();
 }
 
-static void setup_ud_vector(struct kvm_vcpu *vcpu)
-{
-	vm_init_descriptor_tables(vcpu->vm);
-	vcpu_init_descriptor_tables(vcpu);
-	vm_install_exception_handler(vcpu->vm, UD_VECTOR, guest_ud_handler);
-}
-
 static void enter_guest(struct kvm_vcpu *vcpu)
 {
 	struct kvm_run *run = vcpu->run;
@@ -110,35 +103,23 @@ static void enter_guest(struct kvm_vcpu *vcpu)
 	}
 }
 
-static void test_fix_hypercall(void)
+static void test_fix_hypercall(bool disable_quirk)
 {
 	struct kvm_vcpu *vcpu;
 	struct kvm_vm *vm;
 
 	vm = vm_create_with_one_vcpu(&vcpu, guest_main);
-	setup_ud_vector(vcpu);
-
-	ud_expected = false;
-	sync_global_to_guest(vm, ud_expected);
-
-	virt_pg_map(vm, APIC_DEFAULT_GPA, APIC_DEFAULT_GPA);
-
-	enter_guest(vcpu);
-}
-
-static void test_fix_hypercall_disabled(void)
-{
-	struct kvm_vcpu *vcpu;
-	struct kvm_vm *vm;
 
-	vm = vm_create_with_one_vcpu(&vcpu, guest_main);
-	setup_ud_vector(vcpu);
+	vm_init_descriptor_tables(vcpu->vm);
+	vcpu_init_descriptor_tables(vcpu);
+	vm_install_exception_handler(vcpu->vm, UD_VECTOR, guest_ud_handler);
 
-	vm_enable_cap(vm, KVM_CAP_DISABLE_QUIRKS2,
-		      KVM_X86_QUIRK_FIX_HYPERCALL_INSN);
+	if (disable_quirk)
+		vm_enable_cap(vm, KVM_CAP_DISABLE_QUIRKS2,
+			      KVM_X86_QUIRK_FIX_HYPERCALL_INSN);
 
-	ud_expected = true;
-	sync_global_to_guest(vm, ud_expected);
+	quirk_disabled = disable_quirk;
+	sync_global_to_guest(vm, quirk_disabled);
 
 	virt_pg_map(vm, APIC_DEFAULT_GPA, APIC_DEFAULT_GPA);
 
@@ -149,6 +130,6 @@ int main(void)
 {
 	TEST_REQUIRE(kvm_check_cap(KVM_CAP_DISABLE_QUIRKS2) & KVM_X86_QUIRK_FIX_HYPERCALL_INSN);
 
-	test_fix_hypercall();
-	test_fix_hypercall_disabled();
+	test_fix_hypercall(false);
+	test_fix_hypercall(true);
 }