In hopes that the solution may be helpful to others…
User accounts need to be part of the video group.
The default ubuntu account is in this group but I created unique user accounts that needed to be added to the video group as well.
i’m having same issue. got the jetson kit, installed the driver , nothing. what am i doing wrong? i have different version cuda-repo-ubuntun-l4tr-19.2_6.0-42-armhf.deb. going to try again.
i fixed it. d/l the latest cuda toolkit as i have shown above , make sure to CONNECT TO internet. go through nvidia startup guide for L4T section. add the path variables to .bashrc manually. also simliarly to register or add user ‘ubuntu’ then it went throuhg. make some examples and run it like device query. seems to work for me.
I think there are no /dev/nvidia* files but /dev/nvhost* files. But those might be there even without the user space drivers so they might not tell anything about whether or not the user space drivers are installed.