Qt5 QSocketNotifier: Socket notifiers cannot be enabled or disabled from another thread

dl1ksv

I just ported a working Qt4 Application from QT4 to Qt5.
The structure in question is:

   class ProcessLogData : public QThread
   {
   Q_OBJECT
    public:
    ProcessLogData ( QObject *parent = 0 );
    ~ProcessLogData();
    void saveQsoData ( QString s );
    void run();
    void requestCallsign (QLabel **r, QString s );
    private:
    QTcpSocket *tcpSocket;
     ..... some other variables
      private slots:
       void doAction();
       void connectionClosedbyHost();
       void readAnswer();
      void setConnected();
      void setError ( QAbstractSocket::SocketError );
     signals:
       void unabletoConnect();
       void answerAvailable();
       void executeAction();
        };

The main code is:

 ProcessLogData::ProcessLogData ( QObject *parent )
: QThread ( parent )   {
 tcpSocket = 0;
 connectionEstablished = false;
 connectionError = false;
 }
 void ProcessLogData::run() {
  connectionEstablished = false;
  connectionError = false;
  qRegisterMetaType<QAbstractSocket::SocketError> ( "QAbstractSocket::SocketError" );
  tcpSocket = new QTcpSocket();
  connect ( tcpSocket, SIGNAL ( disconnected() ), this, SLOT ( connectionClosedbyHost() ) , Qt::QueuedConnection);
  connect(this,SIGNAL(executeAction()),this,SLOT(doAction()),Qt::QueuedConnection);   
  connect ( tcpSocket, SIGNAL ( readyRead() ), this, SLOT ( readAnswer() ) ,Qt::QueuedConnection);
  connect ( tcpSocket, SIGNAL ( connected() ), this, SLOT ( setConnected() ) ,Qt::QueuedConnection);
 connect ( tcpSocket, SIGNAL ( error ( QAbstractSocket::SocketError ) ), this, SLOT ( setError ( QAbstractSocket::SocketError ) ) );
tcpSocket->connectToHost ( QHostAddress::LocalHost, 8080, QIODevice::ReadWrite );
tcpSocket->waitForConnected(6000);

exec();
}

Data are transferred to the thread by calling:

void ProcessLogData::requestCallsign( ... params ) {
   ...preparing actionString;
   emit executeAction();
 }

Writing to the socket happens in doAction by

  int n = tcpSocket->write ( actionString.toLatin1(), actionString.length() );
  tcpSocket->flush();

write and flush result in a message
QSocketNotifier: Socket notifiers cannot be enabled or disabled from another thread

The data are transferred and the application works.
But what am I doing wrong and how can I avoid the message ?