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I installed the NVIDIA driver 367.44 from the Nvidia site. As a last step I was prompted to disable secure boot on re-boot. I did that, but I am not fully comfortable keeping it disabled. I want to re-enable it and do not know how to.
In anycase, I can not use the Nvidia card for rendering and it only works with the "--no-opengl-files" option. Anything else pushes Ubuntu into a log-in loop.
sudo mokutil --sb-state
But while booting I get an annoying "Booting in insecure mode message"
EDIT: as I understand from the comments this might not pertain to UFEI secure boot, but the MOK secure boot which is needed for Ubuntu to use third party drivers. I am still using 14.04 and keeping the validation enabled did not cause me any issues with my nvidia drivers for CUDA.
I tensorflow/stream_executor/cuda/cuda_gpu_executor.cc:900] successful NUMA node read from SysFS had negative value (-1), but there must be at least one NUMA node, so returning NUMA node zero I tensorflow/core/common_runtime/gpu/gpu_init.cc:102] Found device 0 with properties: name: GeForce 940M major: 5 minor: 0 memoryClockRate (GHz) 1.176 pciBusID 0000:04:00.0 Total memory: 1.96GiB Free memory: 1.94GiB I tensorflow/core/common_runtime/gpu/gpu_init.cc:126] DMA: 0 I tensorflow/core/common_runtime/gpu/gpu_init.cc:136] 0: Y I tensorflow/core/common_runtime/gpu/gpu_device.cc:755] Creating TensorFlow device (/gpu:0) -> (device: 0, name: GeForce 940M, pci bus id: 0000:04:00.0)