@Tomasz Przybysz i915.enable_rc6=0 as a workaround doesn't seem to work. I have similar symptoms as Angelo Lisco. I leave laptop on overnight and sometimes in the morning it got frozen with same underrun error message in logs.
enable_rc6 is definitely set to 0: $ cat /sys/class/drm/card0/power/rc6_enable 0 And the bug is still there with kernel 4.15.10 =( just a heads up -- 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/1550779 Title: [i915]] *ERROR* CPU pipe A FIFO underrun - Xorg glitches Status in linux package in Ubuntu: Incomplete Bug description: Upgraded linux-image-extra-4.2.0-30-generic I see graphic glitches, looks like the graphic buffer gets screwed up - funny repetition's patterns (back in time glitches) - black screen (<1sec) - graphic errors I can influence the severity of the issue with switching windows and using certain programs, e.g. Google Maps in chrome causes this issue reproducibly dmesg | grep i915 [ 2.726864] [drm] Initialized i915 1.6.0 20150522 for 0000:00:02.0 on minor 0 [ 2.792005] [drm] GMBUS [i915 gmbus dpb] timed out, falling back to bit banging on pin 5 [ 3.471092] i915 0000:00:02.0: fb0: inteldrmfb frame buffer device [ 3.471093] i915 0000:00:02.0: registered panic notifier [ 9.573129] [drm:intel_cpu_fifo_underrun_irq_handler [i915]] *ERROR* CPU pipe A FIFO underrun [ 9.574847] [drm:intel_set_pch_fifo_underrun_reporting [i915]] *ERROR* uncleared pch fifo underrun on pch transcoder A [ 9.574895] [drm:intel_pch_fifo_underrun_irq_handler [i915]] *ERROR* PCH transcoder A FIFO underrun linux-image-extra-4.2.0-27-generic works find ProblemType: Bug DistroRelease: Ubuntu 15.10 Package: xorg 1:7.7+7ubuntu4 ProcVersionSignature: Ubuntu 4.2.0-30.36-generic 4.2.8-ckt3 Uname: Linux 4.2.0-30-generic x86_64 .tmp.unity.support.test.0: ApportVersion: 2.19.1-0ubuntu5 Architecture: amd64 BootLog: CompizPlugins: No value set for `/apps/compiz-1/general/screen0/options/active_plugins' CompositorRunning: None CurrentDesktop: GNOME Date: Sat Feb 27 20:26:07 2016 DistUpgraded: Fresh install DistroCodename: wily DistroVariant: ubuntu DkmsStatus: virtualbox, 5.0.14, 4.2.0-27-generic, x86_64: installed virtualbox, 5.0.14, 4.2.0-30-generic, x86_64: installed EcryptfsInUse: Yes ExtraDebuggingInterest: Yes, including running git bisection searches GraphicsCard: Intel Corporation 2nd Generation Core Processor Family Integrated Graphics Controller [8086:0126] (rev 09) (prog-if 00 [VGA controller]) Subsystem: Lenovo Device [17aa:21da] InstallationDate: Installed on 2016-02-11 (15 days ago) InstallationMedia: Ubuntu 15.10 "Wily Werewolf" - Release amd64 (20151021) MachineType: LENOVO 42912XG ProcKernelCmdLine: BOOT_IMAGE=/@/boot/vmlinuz-4.2.0-30-generic root=UUID=cb34d7bb-9316-49b3-aa94-4e2a3512168f ro rootflags=subvol=@ noprompt quiet SourcePackage: xorg UdevLog: Error: [Errno 2] No such file or directory: '/var/log/udev' UpgradeStatus: No upgrade log present (probably fresh install) dmi.bios.date: 07/18/2013 dmi.bios.vendor: LENOVO dmi.bios.version: 8DET69WW (1.39 ) dmi.board.asset.tag: Not Available dmi.board.name: 42912XG dmi.board.vendor: LENOVO dmi.board.version: Not Available dmi.chassis.asset.tag: No Asset Information dmi.chassis.type: 10 dmi.chassis.vendor: LENOVO dmi.chassis.version: Not Available dmi.modalias: dmi:bvnLENOVO:bvr8DET69WW(1.39):bd07/18/2013:svnLENOVO:pn42912XG:pvrThinkPadX220:rvnLENOVO:rn42912XG:rvrNotAvailable:cvnLENOVO:ct10:cvrNotAvailable: dmi.product.name: 42912XG dmi.product.version: ThinkPad X220 dmi.sys.vendor: LENOVO version.compiz: compiz 1:0.9.12.2+15.10.20151202-0ubuntu1 version.ia32-libs: ia32-libs N/A version.libdrm2: libdrm2 2.4.64-1 version.libgl1-mesa-dri: libgl1-mesa-dri 11.0.2-1ubuntu4 version.libgl1-mesa-dri-experimental: libgl1-mesa-dri-experimental N/A version.libgl1-mesa-glx: libgl1-mesa-glx 11.0.2-1ubuntu4 version.xserver-xorg-core: xserver-xorg-core 2:1.17.2-1ubuntu9.1 version.xserver-xorg-input-evdev: xserver-xorg-input-evdev 1:2.9.2-1ubuntu1 version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:7.5.0+git20150819-0ubuntu1 version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.99.917+git20150808-0ubuntu4 version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.11-1ubuntu3 xserver.bootTime: Sat Feb 27 20:25:23 2016 xserver.configfile: default xserver.errors: xserver.logfile: /var/log/Xorg.0.log xserver.outputs: product id 12359 vendor SEC xserver.version: 2:1.17.2-1ubuntu9.1 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1550779/+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