pytorch

1694fde7 - Fix a GroupNorm cuda bug when input does not require_grad (#44863)

Fix a GroupNorm cuda bug when input does not require_grad (#44863) Summary: Fix https://discuss.pytorch.org/t/illegal-memory-access-when-i-use-groupnorm/95800 `dX` is a Tensor, comparing `dX` with `nullptr` was wrong. cc BIT-silence who wrote the kernel. The test couldn't pass with `rtol=0` and `x.requires_grad=True`, so I have to update that to `1e-5`. Pull Request resolved: https://github.com/pytorch/pytorch/pull/44863 Reviewed By: mruberry Differential Revision: D23754101 Pulled By: BIT-silence fbshipit-source-id: 2eb0134dd489480e5ae7113a7d7b84629104cd49