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I have been using Ubuntu 18.04.1 LTS on a Dell Precision 5510 laptop with a Dell Thunderbolt 3 Dock, model TB16, for over two months with no issues. The system is regularly updated with the latest updates.
January 29th 2019, a notification for a new update appeared :
- Several unused kernel files to be deleted
- (update for Oracle's Virtual Box, seems very irrelevant)
I proceeded to install. However after rebooting, reaching the login screen and entering my password, I only had black screens and a completely unresponsive system.
After several reboots and attempts to diagnose the problem, only when I rebooted the system with the Dell Thunderbolt 3 Dock unplugged that the system successfully booted and displayed the desktop, menu bar...etc. Even then, when I re-plugged the dock, the system became unresponsive with a black screen.
I am currently looking into restoring the pre-update kernel using GRUB.
I'm interested to know if anyone, with a relatively similar setup, is experiencing this issue. Any other insights or ideas that could help are welcome.
Another report on this issue found (2 posts by the same author), it seems to affect only Dell docks but it is probably not restricted to Dell machines:
For now the issue has been resolved by restoring 4.15.0-43-generic using GRUB. I am holding from updating Ubuntu until the bug gets fixed.