UI becomes completely unresponsive

[Amy Codeplay]

Starting from last Friday, i have had problems with Ubuntu freezing up. Although the mouse pointer still moves, clicking on things does not work. I was able to get to text mode terminal using Ctrl+Alt+Fx keys and shut down from the command line, which seemed to be unaffected. Shutting down took ages. Upon logging in again, it hung immediately as soon as the desktop loaded and i was not able to launch any applications or shut down from the UI, in fact this time i was not able to get to the text mode terminals either and had to shut down using the power button.

I have since been booting from an earlier version of the kernel without issue (-147 instead of -151). This morning i tried 151 again and it immediately froze up upon logging in, before the desktop had loaded, and even the mouse pointer was frozen this time. Had to hard-reboot and booted
back into -147 just fine.

Hardware is a Dell Latitude E7470

[Amy Codeplay (amy-codeplay)]

There are multiple crash logs in /var/crash, all from Friday when it first happened. Later episodes seem to not have created a crash log.

[Ubuntu Foundations Team Bug Bot (crichton)]

Thank you for taking the time to report this bug and helping to make Ubuntu better. It seems that your bug report is not filed about a specific source package though, rather it is just filed against Ubuntu in general. It is important that bug reports be filed about source packages so that people interested in the package can find the bugs about it. You can find some hints about determining what package your bug might be about at https://wiki.ubuntu.com/Bugs/FindRightPackage. You might also ask for help in the #ubuntu-bugs irc channel on Freenode.

To change the source package that this bug is filed about visit https://bugs.launchpad.net/ubuntu/+bug/1938275/+editstatus and add the package name in the text box next to the word Package.

[This is an automated message. I apologize if it reached you inappropriately; please just reply to this message indicating so.]

[Amy Codeplay (amy-codeplay)]

Thanks Bug Bot, the problem is not with a specific source package but with Ubuntu itself, specifically kernel version 4.15.0-151

[Paul White (paulw2u)]

Amy, if you have concluded that the package that you are reporting your issue against is the kernel then the bug report needs to be assigned to "linux". I have done this for you. The kernel bot will shortly ask you for further information, mark the report as being 'Incomplete' and ask you to update the status of the bug report.

Please follow these instructions so that this bug report reaches a member of the Kernel Team.

[Benno Schulenberg (bennoschulenberg)]

A very similr issue was reported in bug #1938430: a kernel oops or a complete freeze upon resuming from suspension.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Benno Schulenberg (bennoschulenberg)]

It seems likely that this is a duplicate of bug #1938013: kernel 4.15.0-151 is freezing various CPUs.