[drm:intel_cpu_fifo_underrun_irq_handler [i915]] *ERROR* CPU pipe A FIFO underrun

[amichair]

On Kubuntu 15.10, KDE Framework 5.18.0, Qt 5.5.1, kernel 4.4.1-040401-generic from http://kernel.ubuntu.com/~kernel-ppa/mainline/ (I upgraded hoping it would solve the problem, but it did not). Haswell i7-4771 with integrated GPU (no other graphics card). 3-monitor setup.

Several times a day the display seems to crash in various ways, some recoverable (e.g. by restarting plasmashell or sddm) but sometimes a monitor stays blank, corrupt or unresponsive and only a full reboot helps. I also see a plasma crash dialog every time I return to my desktop after the screens went into power-savings mode when I was away (I don't know if this is related or a plasma bug). It also happens sometimes while dragging a windows (desktop effects are on), while watching a video (I now get occasionally a few seconds with black output in the middle of the video too). It's hard to pinpoint which components are unstable, likely more than one, but this is a starting point since I get the following message in dmesg which I assume is at a lower level than the desktop environment (correct me if I'm wrong):

[Thu Feb 4 10:44:20 2016] [drm:intel_set_cpu_fifo_underrun_reporting [i915]] *ERROR* uncleared fifo underrun on pipe A
[Thu Feb 4 10:44:20 2016] [drm:intel_cpu_fifo_underrun_irq_handler [i915]] *ERROR* CPU pipe A FIFO underrun

[amichair (amichai2)]

Note to self (apparently): A workaround that brings back the windows without losing any data from open apps, at least in some cases, is running "DISPLAY=:0 kwin_x11 --replace" from the terminal (ctrl-alt-f1).

[penalvch (penalvch)]

amichair, thank you for reporting this and helping make Ubuntu better.

Could you please run the following command once from a terminal by ensuring you have the package xdiagnose installed, and that you click the Yes button for attaching additional debugging information:
apport-collect -p xorg 1541751

When reporting xorg related bugs in the future, please do so via the above method. You can learn more about this functionality at https://wiki.ubuntu.com/ReportingBugs.

[amichair (amichai2)]

After upgrade to Kubuntu 16.04 with kernel 4.4.6-040406-generic, the crashes seem to have stopped, although the error messages are still there. Maybe they were unrelated, or maybe the error is handled more gracefully now...

[Launchpad Janitor (janitor)]

[Expired for xorg (Ubuntu) because there has been no activity for 60 days.]