@ptrblck
I successfully build PyTorch from source with CUDA 11. However, I still got:
➜  pytorch python
Python 3.8.2 (default, Jul 16 2020, 14:00:26) 
[GCC 9.3.0] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> import torch
>>> torch.cuda
<module 'torch.cuda' from '/home/jiapei/.local/lib/python3.8/site-packages/torch/cuda/__init__.py'>
>>> torch.cuda.is_available()
False
>>> print(torch.version.cuda)
11.0
>>> torch.backends.cudnn.enabled
True
>>> 

Clearly, the output of torch.cuda.is_available() returned False, which is incorrect.
Any further suggestions?