Issue description

Inf become not inf after taking torch.max under gpu

Code example

import torch
x = torch.full((10,10), float('-inf')).cuda()
print(x.max(1)[0])

System Info

PyTorch version: 0.4.1
Is debug build: No
CUDA used to build PyTorch: 9.0.176

OS: Ubuntu 16.04.4 LTS
GCC version: (Ubuntu 5.4.0-6ubuntu1~16.04.9) 5.4.0 20160609
CMake version: version 3.5.1

Python version: 3.6
Is CUDA available: Yes
CUDA runtime version: 9.0.176
GPU models and configuration:
GPU 0: Tesla P100-PCIE-16GB
GPU 1: Tesla P100-PCIE-16GB

Nvidia driver version: 384.111
cuDNN version: Probably one of the following:
/usr/lib/x86_64-linux-gnu/libcudnn.so.7.1.4
/usr/lib/x86_64-linux-gnu/libcudnn_static_v7.a

Versions of relevant libraries:
[pip] numpy (1.14.0)
[pip] numpydoc (0.7.0)
[pip] torch (0.4.1)
[pip] torchtext (0.2.3)
[pip] torchvision (0.2.1)
[conda] pytorch 0.4.1 py36_cuda9.0.176_cudnn7.1.2_1 pytorch
[conda] torchtext 0.2.3
[conda] torchvision 0.2.1 py36_1 pytorch