Seems like the repos for CUDA 9 adn TensorRT has missing invalid public keys??
On apt-get update, I get the following errors…
W: GPG error: file:/var/cuda-repo-9-0-local Release: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY F60F4B3D7FA2AF80
W: The repository 'file:/var/cuda-repo-9-0-local Release' is not signed.
N: Data from such a repository can't be authenticated and is therefore potentially dangerous to use.
N: See apt-secure(8) manpage for repository creation and user configuration details.
W: GPG error: file:/var/nv-tensorrt-repo-ga-cuda9.0-trt3.0.4-20180208 Release: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY F60F4B3D7FA2AF80
W: The repository 'file:/var/nv-tensorrt-repo-ga-cuda9.0-trt3.0.4-20180208 Release' is not signed.
N: Data from such a repository can't be authenticated and is therefore potentially dangerous to use.
N: See apt-secure(8) manpage for repository creation and user configuration details.