From da8453af6eb071ee988bdea1154fbbcbe460f053 Mon Sep 17 00:00:00 2001
From: Sandeep Rajan <srajan@infoblox.com>
Date: Thu, 27 Feb 2020 10:39:47 -0500
Subject: [PATCH] fix unsupported bug

---
 cmd/kubeadm/app/phases/upgrade/preflight.go | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/cmd/kubeadm/app/phases/upgrade/preflight.go b/cmd/kubeadm/app/phases/upgrade/preflight.go
index 0351650ccf3..913fd2313cd 100644
--- a/cmd/kubeadm/app/phases/upgrade/preflight.go
+++ b/cmd/kubeadm/app/phases/upgrade/preflight.go
@@ -85,7 +85,7 @@ func checkUnsupportedPlugins(client clientset.Interface) error {
 	if err != nil {
 		return err
 	}
-	if unsupportedCoreDNS != nil {
+	if len(unsupportedCoreDNS) != 0 {
 		var UnsupportedPlugins []string
 		for _, unsup := range unsupportedCoreDNS {
 			UnsupportedPlugins = append(UnsupportedPlugins, unsup.ToString())