** Description changed: I maintain a set of older kiosks running a mix of stock Ubuntu 14.04 LTS and 16.04. As we have gradually transitioned them to 16.04, we have - noticed that the machines running 16.04.3 now regularly exhibit problems + noticed that the machines running 16.04.1 now regularly exhibit problems restoring from the blank screen which appears after a period of inactivity. This only occurs on the machines where we've installed 16.04. All of - the 16.04.3 installations are "fresh", that is, complete re-installs + the 16.04.1 installations are "fresh", that is, complete re-installs from scratch, and we install all security and other updates on a regular basis. This problem has persisted right from the beginning when we started using 16.04. Following a period of user inactivity, the screen goes blank; this is, of course, expected. When the user tries to restore the session by typing a key or moving the mouse, one of three outcomes occurs. Sometimes, the session restores normally. Other times, the screen remains blank regardless of all normal keyboard input, until a magic SysRq sequence is performed. After Alt-SysRq-k, either the virtual console resets to a login screen (as expected after this SysRq sequence), or we get a kernel panic text screen (see attached screen photo) and can only restore via a hard power-cycle reboot. I will continue to try to capture a better trace output from one of these conditions, perhaps from /var/log/kern.log or by installing linux- crashdump (although these old machines may not have enough memory for the stock package). But in the meantime, I'm attaching a photo of the kernel panic we see, which suggests a problem may reside in the Radeon driver ... which would seem possible, given the general blank-screen no- resume problem on these systems. Any advice on how to further capture any other needed details would be appreciated. Thanks very much!
-- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1763273 Title: kernel panic in Radeon driver while screen blank To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1763273/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs