- Moved the gradient unscaling in `NativeMixedPrecisionPlugin` from `pre_optimizer_step` to `post_backward` ([9606](https://github.com/PyTorchLightning/pytorch-lightning/pull/9606))
- Fixed gradient unscaling being called too late, causing gradient clipping and gradient norm tracking to be applied incorrectly ([9606](https://github.com/PyTorchLightning/pytorch-lightning/pull/9606))
- Fixed `lr_find` to generate same results on multiple calls ([9704](https://github.com/PyTorchLightning/pytorch-lightning/pull/9704))
- Fixed `reset` metrics on validation epoch end ([9717](https://github.com/PyTorchLightning/pytorch-lightning/pull/9717))
- Fixed input validation for `gradient_clip_val`, `gradient_clip_algorithm`, `track_grad_norm` and `terminate_on_nan` Trainer arguments ([9595](https://github.com/PyTorchLightning/pytorch-lightning/pull/9595))
- Reset metrics before each task starts ([9410](https://github.com/PyTorchLightning/pytorch-lightning/pull/9410))
Contributors
rohitgr7 tchaton
_If we forgot someone due to not matching commit email with GitHub account, let us know :]_