As CUDA 6.5 is officially released, I started a fresh AWS EC2 g2.2xlarge instance, installed Ubuntu 14.04.1 LTS.
I fully upgraded the OS. I installed the 4 packages Ubuntu wanted to withdraw from upgrade (linux-virtual, linux-kernel-virtual, etc.)
Then I installed cuda using the official .deb. Now again, whatever I do (nvidia-modprobe, nvidia-smi), I get the error message
modprobe: ERROR: could not insert ‘nvidia_340’: Unknown symbol in module, or unknown parameter (see dmesg)
I thus checked dmesg, I found the cause was that drm.ko was missing. I googled on web but I don’t find any solution. CUDA 6.0 works well with Ubuntu 12.04 on AWS EC2 because the OS was able to launch both the nvidia and drm kernel modules.
I’m not even sure whether I should ask Ubuntu, AWS, or Nvidia for help.