Takashi, Since it looks like the patch for this is still in the pipeline for a fix in 5.5, I thought I'd try to get ahead of an issue that will arise there. I mentioned before that the only problem I was experiencing with 5.5 was that I needed to reinstall nvidia/bumblebee. It turns out that the _actual problem_ is that nvidia drivers will not build on 5.5. There is a patch, but nvidia seems to be planning to wait until <after v440.44> to implement it. Our bumblebee driver is currently at 418.113. https://devtalk.nvidia.com/default/topic/1068332/linux/nvidia-driver-does-not-build-on-linux-v5-5-release-candidate-kernel/ So, not much to look forward to in 5.5, I'm afraid.