EvalResult can't log 2D tensor
I want to calculate confusion matrix in test step, but EvalResult can't log it.  How can I do to store it in EvalResult? If I have to override test_epoch_end, what should I do to process logged metric and my confusion matrix as default behaviour?
    def test_step(self, batch, batch_idx):
        result = pl.EvalResult()
        result.log('test_loss', loss, sync_dist=True)
        result.log('test_vacc', vid_acc, sync_dist=True)
        #result.log('confusionmatrix', cm, sync_dist=True, sync_dist_op=torch.distributed.ReduceOp.SUM)
        return result