diff --git a/pytorch_lightning/models/trainer.py b/pytorch_lightning/models/trainer.py
index 7c45f35a..3b129d78 100644
--- a/pytorch_lightning/models/trainer.py
+++ b/pytorch_lightning/models/trainer.py
@@ -150,6 +150,9 @@ class Trainer(TrainerIO):
         self.use_ddp = False
         self.use_dp = False
 
+        # bookkeeping
+        self.avg_loss = 0
+
 
         # gpus come in as a string.
         # if gpus = -1 then use all available devices
diff --git a/tests/test_models.py b/tests/test_models.py
index e0b0a36e..6bac63cf 100644
--- a/tests/test_models.py
+++ b/tests/test_models.py
@@ -227,7 +227,6 @@ def test_amp_gpu_dp():
         experiment=get_exp(),
         max_nb_epochs=1,
         train_percent_check=0.4,
-        val_percent_check=0.4,
         gpus=[0, 1],
         distributed_backend='dp',
         use_amp=True