I am having the exact same problem with CUDA 10.2 on opensuse tumbleweed. Using the latest nvidia drivers 440.82. I compiled the CUDA samples with gcc-7 which worked. When calling ./deviceQuery I get the same error message.
However, I can run ./deviceQuery as root and after I doing this once it also works as a normal user. And magically, all of a sudden blender finds my CUDA device and everything is fine until next reboot. Then I have to run ./deviceQuery as root again to get CUDA to recognize my GPU.