Revert "Remove untainting logic."

This reverts a part of commit eec47aa.

pkg/minikube/bootstrapper/kubeadm/kubeadm.go

@@ -135,6 +135,14 @@ func (k *KubeadmBootstrapper) StartCluster(k8s config.KubernetesConfig) error {
 		return errors.Wrapf(err, "kubeadm init error %s running command: %s", b.String(), out)
 	}
 
+	if version.LT(semver.MustParse("1.10.0-alpha.0")) {
+		//TODO(r2d4): get rid of global here
+		master = k8s.NodeName
+		if err := util.RetryAfter(200, unmarkMaster, time.Second*1); err != nil {
+			return errors.Wrap(err, "timed out waiting to unmark master")
+		}
+	}
+
 	if err := util.RetryAfter(100, elevateKubeSystemPrivileges, time.Millisecond*500); err != nil {
 		return errors.Wrap(err, "timed out waiting to elevate kube-system RBAC privileges")
 	}

pkg/minikube/bootstrapper/kubeadm/util.go

@@ -18,24 +18,78 @@ package kubeadm
 
 import (
 	"bytes"
+	"encoding/json"
 	"html/template"
 	"strings"
 
 	"github.com/golang/glog"
 	"github.com/pkg/errors"
+	clientv1 "k8s.io/api/core/v1"
 	rbacv1beta1 "k8s.io/api/rbac/v1beta1"
+	apierrs "k8s.io/apimachinery/pkg/api/errors"
 	"k8s.io/apimachinery/pkg/apis/meta/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/labels"
+	"k8s.io/apimachinery/pkg/types"
+	"k8s.io/apimachinery/pkg/util/strategicpatch"
 	"k8s.io/minikube/pkg/minikube/config"
 	"k8s.io/minikube/pkg/minikube/service"
 	"k8s.io/minikube/pkg/util"
 )
 
 const (
-	rbacName = "minikube-rbac"
+	masterTaint = "node-role.kubernetes.io/master"
+	rbacName    = "minikube-rbac"
 )
 
+var master = ""
+
+func unmarkMaster() error {
+	k8s := service.K8s
+	client, err := k8s.GetCoreClient()
+	if err != nil {
+		return errors.Wrap(err, "getting core client")
+	}
+	n, err := client.Nodes().Get(master, v1.GetOptions{})
+	if err != nil {
+		return errors.Wrapf(err, "getting node %s", master)
+	}
+
+	oldData, err := json.Marshal(n)
+	if err != nil {
+		return errors.Wrap(err, "json marshalling data before patch")
+	}
+
+	newTaints := []clientv1.Taint{}
+	for _, taint := range n.Spec.Taints {
+		if taint.Key == masterTaint {
+			continue
+		}
+
+		newTaints = append(newTaints, taint)
+	}
+	n.Spec.Taints = newTaints
+
+	newData, err := json.Marshal(n)
+	if err != nil {
+		return errors.Wrapf(err, "json marshalling data after patch")
+	}
+
+	patchBytes, err := strategicpatch.CreateTwoWayMergePatch(oldData, newData, clientv1.Node{})
+	if err != nil {
+		return errors.Wrap(err, "creating strategic patch")
+	}
+
+	if _, err := client.Nodes().Patch(n.Name, types.StrategicMergePatchType, patchBytes); err != nil {
+		if apierrs.IsConflict(err) {
+			return errors.Wrap(err, "strategic patch conflict")
+		}
+		return errors.Wrap(err, "applying strategic patch")
+	}
+
+	return nil
+}
+
 // elevateKubeSystemPrivileges gives the kube-system service account
 // cluster admin privileges to work with RBAC.
 func elevateKubeSystemPrivileges() error {