Ubuntu cannot access the system after apt-get upgrade. ubuntu-get

Ubuntu cannot access the system after apt-get upgrade. ubuntu-get

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A few days ago, I had a poor hand base and obsessive-compulsive disorder. When I updated and upgrade ubuntu, I was unable to enter the system. After Entering the password on the login interface, I kept getting stuck, I found more than N solutions on the Intranet and Internet. After a day of hard work, I still had no solution. I had to reinstall it. However, you have to reconfigure the caffe environment again.

However, we found a note when reinstalling the nvidia driver:

After each kernel upgrade, you must re-compile the graphics card driver... Restricted driver list (source) is okay.

I don't know if I can't start the system, because I didn't re-compile the graphics card driver, so I upgraded the kernel by upgrade.