KVM: selftests: Convert state_test away from VCPU_ID

Convert state_test to use vm_create_with_one_vcpu() and
vm_recreate_with_one_vcpu(), and pass around a 'struct kvm_vcpu' object
instead of using a global VCPU_ID.  Note, this is a "functional" change
in the sense that the test now creates a vCPU with vcpu_id==0 instead of
vcpu_id==5.  The non-zero VCPU_ID was 100% arbitrary and added little to
no validation coverage.  If testing non-zero vCPU IDs is desirable for
generic tests, that can be done in the future by tweaking the VM creation
helpers.

Opportunistically use vcpu_run() instead of _vcpu_run(), the test expects
KVM_RUN to succeed.
Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

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

@@ -20,7 +20,6 @@
 #include "vmx.h"
 #include "svm_util.h"
 
-#define VCPU_ID		5
 #define L2_GUEST_STACK_SIZE 256
 
 void svm_l2_guest_code(void)
@@ -157,6 +156,7 @@ int main(int argc, char *argv[])
 	vm_vaddr_t nested_gva = 0;
 
 	struct kvm_regs regs1, regs2;
+	struct kvm_vcpu *vcpu;
 	struct kvm_vm *vm;
 	struct kvm_run *run;
 	struct kvm_x86_state *state;
@@ -164,10 +164,10 @@ int main(int argc, char *argv[])
 	int stage;
 
 	/* Create VM */
-	vm = vm_create_default(VCPU_ID, 0, guest_code);
-	run = vcpu_state(vm, VCPU_ID);
+	vm = vm_create_with_one_vcpu(&vcpu, guest_code);
+	run = vcpu->run;
 
-	vcpu_regs_get(vm, VCPU_ID, &regs1);
+	vcpu_regs_get(vm, vcpu->id, &regs1);
 
 	if (kvm_check_cap(KVM_CAP_NESTED_STATE)) {
 		if (nested_svm_supported())
@@ -179,16 +179,16 @@ int main(int argc, char *argv[])
 	if (!nested_gva)
 		pr_info("will skip nested state checks\n");
 
-	vcpu_args_set(vm, VCPU_ID, 1, nested_gva);
+	vcpu_args_set(vm, vcpu->id, 1, nested_gva);
 
 	for (stage = 1;; stage++) {
-		_vcpu_run(vm, VCPU_ID);
+		vcpu_run(vm, vcpu->id);
 		TEST_ASSERT(run->exit_reason == KVM_EXIT_IO,
 			    "Stage %d: unexpected exit reason: %u (%s),\n",
 			    stage, run->exit_reason,
 			    exit_reason_str(run->exit_reason));
 
-		switch (get_ucall(vm, VCPU_ID, &uc)) {
+		switch (get_ucall(vm, vcpu->id, &uc)) {
 		case UCALL_ABORT:
 			TEST_FAIL("%s at %s:%ld", (const char *)uc.args[0],
 			       	  __FILE__, uc.args[1]);
@@ -206,22 +206,21 @@ int main(int argc, char *argv[])
 			    uc.args[1] == stage, "Stage %d: Unexpected register values vmexit, got %lx",
 			    stage, (ulong)uc.args[1]);
 
-		state = vcpu_save_state(vm, VCPU_ID);
+		state = vcpu_save_state(vm, vcpu->id);
 		memset(&regs1, 0, sizeof(regs1));
-		vcpu_regs_get(vm, VCPU_ID, &regs1);
+		vcpu_regs_get(vm, vcpu->id, &regs1);
 
 		kvm_vm_release(vm);
 
 		/* Restore state in a new VM.  */
-		kvm_vm_restart(vm);
-		vm_vcpu_add(vm, VCPU_ID);
-		vcpu_set_cpuid(vm, VCPU_ID, kvm_get_supported_cpuid());
-		vcpu_load_state(vm, VCPU_ID, state);
-		run = vcpu_state(vm, VCPU_ID);
+		vcpu = vm_recreate_with_one_vcpu(vm);
+		vcpu_set_cpuid(vm, vcpu->id, kvm_get_supported_cpuid());
+		vcpu_load_state(vm, vcpu->id, state);
+		run = vcpu->run;
 		kvm_x86_state_cleanup(state);
 
 		memset(&regs2, 0, sizeof(regs2));
-		vcpu_regs_get(vm, VCPU_ID, &regs2);
+		vcpu_regs_get(vm, vcpu->id, &regs2);
 		TEST_ASSERT(!memcmp(&regs1, &regs2, sizeof(regs2)),
 			    "Unexpected register values after vcpu_load_state; rdi: %lx rsi: %lx",
 			    (ulong) regs2.rdi, (ulong) regs2.rsi);