@@ -850,7 +850,6 @@ func parallelJoin(t *testing.T, rc libnetwork.Sandbox, ep libnetwork.Endpoint, t

 	err = ep.Join(sb)

 	runtime.LockOSThread()

-	defer runtime.UnlockOSThread()

 	if err != nil {

 		if _, ok := err.(types.ForbiddenError); !ok {

 			t.Fatalf("thread %d: %v", thrNumber, err)

@@ -868,7 +867,6 @@ func parallelLeave(t *testing.T, rc libnetwork.Sandbox, ep libnetwork.Endpoint,

 	err = ep.Leave(sb)

 	runtime.LockOSThread()

-	defer runtime.UnlockOSThread()

 	if err != nil {

 		if _, ok := err.(types.ForbiddenError); !ok {

 			t.Fatalf("thread %d: %v", thrNumber, err)

@@ -39,6 +39,19 @@ func Init() {

 	}

 }

+// SetNamespace sets the initial namespace handler

+func SetNamespace() error {

+	initOnce.Do(Init)

+	if err := netns.Set(initNs); err != nil {

+		linkInfo, linkErr := getLink()

+		if linkErr != nil {

+			linkInfo = linkErr.Error()

+		}

+		return fmt.Errorf("failed to set to initial namespace, %v, initns fd %d: %v", linkInfo, initNs, err)

+	}

+	return nil

+}

+

 // ParseHandlerInt transforms the namespace handler into an integer

 func ParseHandlerInt() int {

 	return int(getHandler())

@@ -424,10 +424,13 @@ func (n *networkNamespace) InvokeFunc(f func()) error {

 // InitOSContext initializes OS context while configuring network resources

 func InitOSContext() func() {

 	runtime.LockOSThread()

+	if err := ns.SetNamespace(); err != nil {

+		logrus.Error(err)

+	}

 	return runtime.UnlockOSThread

 }

-func nsInvoke(path string, prefunc, postfunc func(int) error) error {

+func nsInvoke(path string, prefunc func(nsFD int) error, postfunc func(callerFD int) error) error {

 	defer InitOSContext()()

 	newNs, err := netns.GetFromPath(path)

@@ -442,17 +445,10 @@ func nsInvoke(path string, prefunc, postfunc func(int) error) error {

 		return fmt.Errorf("failed in prefunc: %v", err)

 	}

-	// save the current namespace (host namespace)

-	curNs, err := netns.Get()

-	if err != nil {

-		return err

-	}

-	defer curNs.Close()

 	if err = netns.Set(newNs); err != nil {

 		return err

 	}

-	// will restore the previous namespace before unlocking the thread

-	defer netns.Set(curNs)

+	defer ns.SetNamespace()

 	// Invoked after the namespace switch.

 	return postfunc(ns.ParseHandlerInt())

@@ -7,6 +7,7 @@ import (

 	"net"

 	"os"

 	"path/filepath"

+	"runtime"

 	"strings"

 	"syscall"

 	"testing"

@@ -198,6 +199,7 @@ func TestDisableIPv6DAD(t *testing.T) {

 	if err != nil {

 		t.Fatalf("Failed to create a new sandbox: %v", err)

 	}

+	runtime.LockOSThread()

 	defer s.Destroy()

 	n, ok := s.(*networkNamespace)

@@ -251,6 +253,7 @@ func TestSetInterfaceIP(t *testing.T) {

 	if err != nil {

 		t.Fatalf("Failed to create a new sandbox: %v", err)

 	}

+	runtime.LockOSThread()

 	defer s.Destroy()

 	n, ok := s.(*networkNamespace)

@@ -326,6 +329,7 @@ func TestLiveRestore(t *testing.T) {

 	if err != nil {

 		t.Fatalf("Failed to create a new sandbox: %v", err)

 	}

+	runtime.LockOSThread()

 	defer s.Destroy()

 	n, ok := s.(*networkNamespace)

@@ -2,6 +2,7 @@ package osl

 import (

 	"os"

+	"runtime"

 	"testing"

 	"github.com/docker/docker/pkg/reexec"

@@ -79,6 +80,7 @@ func TestSandboxCreateTwice(t *testing.T) {

 	if err != nil {

 		t.Fatalf("Failed to create a new sandbox: %v", err)

 	}

+	runtime.LockOSThread()

 	// Create another sandbox with the same key to see if we handle it

 	// gracefully.

@@ -86,6 +88,7 @@ func TestSandboxCreateTwice(t *testing.T) {

 	if err != nil {

 		t.Fatalf("Failed to create a new sandbox: %v", err)

 	}

+	runtime.LockOSThread()

 	err = s.Destroy()

 	if err != nil {

@@ -127,6 +130,7 @@ func TestAddRemoveInterface(t *testing.T) {

 	if err != nil {

 		t.Fatalf("Failed to create a new sandbox: %v", err)

 	}

+	runtime.LockOSThread()

 	if s.Key() != key {

 		t.Fatalf("s.Key() returned %s. Expected %s", s.Key(), key)

@@ -33,6 +33,8 @@ func SetupTestOSContext(t *testing.T) func() {

 	// sure to re-initialize initNs context

 	ns.Init()

+	runtime.LockOSThread()

+

 	return func() {

 		if err := syscall.Close(fd); err != nil {

 			t.Logf("Warning: netns closing failed (%v)", err)