Alexander Kops, yes please. Also, it would be helpful to attach the information via SSH or netconsole via https://help.ubuntu.com/community/DebuggingSystemCrash .
In addition, to follow up: 1) Have the issues happened without having to lock the computer (i.e. during active daily use, with the PC in or not in the docking station)? No need for a test to this specifically, just as per your recollection? 2) When the computer is plugged into the docking station, does the OS recognize this by showing the battery icon in a charging/charged state? 3) Does this issue happen if you don't dock the computer in the docking station, and only have the power cord plugged into the computer directly (i.e. no external monitors plugged)? 4) Does the issue happen bypassing the docking station, and plugging the monitors and power directly into the laptop? 5) Does this issue happen if the PC has nothing connected (i.e. keep it on battery, and no external monitors)? 6) Regarding your question in https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1727662/comments/12 : >"Can you advise on how to narrow down the error to the actual state where it >happens?" What seems strange is how after locking the computer with it plugged into the docking station, presuming the power cord is plugged into the docking station, there are a few events in order of most to least interest: * The PC is set to suspend on battery. I originally presumed that this is the issue trigger, but was thrown off as the GUI screenshots are set to do this only on battery. * The screen dims when inactive. You could try rapidly toggling the brightness max up/down. * The WiFi turning off. You could try toggling the WiFi hard swich/key combo repeatedly. * The lock event itself. You could try locking and immediately unlocking multiple times in quick succession. -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1727662 Title: Crashes after unlock: [drm:intel_cpu_fifo_underrun_irq_handler [i915]] *ERROR* CPU pipe A FIFO underrun Status in linux package in Ubuntu: Incomplete Bug description: After upgrading from Ubtuntu 17.04 to Ubuntu 17.10 this bug started appearing. When I lock my screen on my Lenovo T450s and the notebook sits in the dock (two external screens attached), one of the three things happen when I come back after some time and try to unlock (so it went to power save in-between): * Most of the time the computer was just shut down and I have to start it again * Sometimes the notebook screen flickers weirdly and one of the two other screens show pixel garbage * The notebook screen shows the lock screen but is completely frozen. Occasionally unlocking also works. The last thing I find in /var/log/syslog is [drm:intel_cpu_fifo_underrun_irq_handler [i915]] *ERROR* CPU pipe A FIFO underrun [drm:intel_cpu_fifo_underrun_irq_handler [i915]] *ERROR* CPU pipe B FIFO underrun Using or not using the following kernel parameter didn't change anything: i915.enable_rc6=0 ProblemType: Bug DistroRelease: Ubuntu 17.10 Package: linux-image-4.13.0-16-lowlatency 4.13.0-16.19 ProcVersionSignature: Ubuntu 4.13.0-16.19-lowlatency 4.13.4 Uname: Linux 4.13.0-16-lowlatency x86_64 ApportVersion: 2.20.7-0ubuntu3 Architecture: amd64 AudioDevicesInUse: USER PID ACCESS COMMAND /dev/snd/controlC1: akops 3337 F.... pulseaudio /dev/snd/controlC0: akops 3337 F.... pulseaudio CurrentDesktop: ubuntu:GNOME Date: Thu Oct 26 10:44:11 2017 HibernationDevice: RESUME=/dev/mapper/system-swap_1 MachineType: LENOVO 20BWS2YL00 ProcFB: 0 inteldrmfb ProcKernelCmdLine: BOOT_IMAGE=/vmlinuz-4.13.0-16-lowlatency root=/dev/mapper/system-root ro quiet splash i915.enable_rc6=0 crashkernel=384M-:128M vt.handoff=7 RelatedPackageVersions: linux-restricted-modules-4.13.0-16-lowlatency N/A linux-backports-modules-4.13.0-16-lowlatency N/A linux-firmware 1.169 SourcePackage: linux UpgradeStatus: Upgraded to artful on 2017-10-20 (5 days ago) dmi.bios.date: 07/08/2015 dmi.bios.vendor: LENOVO dmi.bios.version: JBET51WW (1.16 ) dmi.board.asset.tag: Not Available dmi.board.name: 20BWS2YL00 dmi.board.vendor: LENOVO dmi.board.version: SDK0E50510 WIN dmi.chassis.asset.tag: No Asset Information dmi.chassis.type: 10 dmi.chassis.vendor: LENOVO dmi.chassis.version: None dmi.modalias: dmi:bvnLENOVO:bvrJBET51WW(1.16):bd07/08/2015:svnLENOVO:pn20BWS2YL00:pvrThinkPadT450s:rvnLENOVO:rn20BWS2YL00:rvrSDK0E50510WIN:cvnLENOVO:ct10:cvrNone: dmi.product.family: ThinkPad T450s dmi.product.name: 20BWS2YL00 dmi.product.version: ThinkPad T450s dmi.sys.vendor: LENOVO To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1727662/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
