the workaround was the same as described in https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1491467
echo "disable" > /sys/firmware/acpi/interrupts/gpe13 ** Description changed: I see high cpu usage from a kworker thread. Usually kworker/0:1 or kworker/0:2. I tested various kernels from Ubuntu and mainline (3.5.0-x, 3.6.x, 3.7.0-rcx) and they all showed the same behavior. This does not always happen. I wasn't able to determine on which basis it happens. Some observations that may as well be wrong (duh!): On some boot all is fine but once it shows, no matter how many reboots it does not seem to want to go away again. The laptop seems to have to rest a while to have a chance that it won't happen. If it does not happen a reboot will show the behavior. I saw similar bug reports in various places but it seems that this can have a multitude of causes and the presented workarounds or fixes did not apply to me. ProblemType: Bug DistroRelease: Ubuntu 12.10 Package: linux-image-3.5.0-19-generic 3.5.0-19.30 ProcVersionSignature: Ubuntu 3.5.0-19.30-generic 3.5.7 Uname: Linux 3.5.0-19-generic x86_64 ApportVersion: 2.6.1-0ubuntu6 Architecture: amd64 AudioDevicesInUse: USER PID ACCESS COMMAND /dev/snd/controlC0: mio 1965 F.... pulseaudio /dev/snd/pcmC0D0p: mio 1965 F...m pulseaudio Date: Wed Dec 5 22:37:00 2012 HibernationDevice: RESUME=UUID=a371882c-0fe7-45e5-9adb-83da8374bc11 InstallationDate: Installed on 2012-10-10 (55 days ago) InstallationMedia: Ubuntu 12.04.1 LTS "Precise Pangolin" - Release amd64 (20120823.1) MachineType: SAMSUNG ELECTRONICS CO., LTD. 700Z7C MarkForUpload: True ProcEnviron: TERM=xterm PATH=(custom, no user) LANG=en_US.UTF-8 SHELL=/bin/bash ProcFB: 0 inteldrmfb ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.5.0-19-generic root=UUID=79674508-93de-43e0-b313-f6a9b480c606 ro crashkernel=384M-2G:64M,2G-:128M acpi_osi=Linux pcie_aspm=force i915.modeset=1 i915.i915_enable_rc6=1 i915.lvds_downclock=1 i915.semaphores=1 i915.powersave=1 snd_hda_intel.power_save_controller=1 snd_hda_intel.power_save=1 quiet splash vt.handoff=7 PulseList: Error: command ['pacmd', 'list'] failed with exit code 1: Home directory /home/mio not ours. No PulseAudio daemon running, or not running as session daemon. RelatedPackageVersions: linux-restricted-modules-3.5.0-19-generic N/A linux-backports-modules-3.5.0-19-generic N/A linux-firmware 1.95 SourcePackage: linux UpgradeStatus: Upgraded to quantal on 2012-10-11 (55 days ago) dmi.bios.date: 08/02/2012 dmi.bios.vendor: Phoenix Technologies Ltd. dmi.bios.version: P04AAE dmi.board.asset.tag: Base Board Asset Tag dmi.board.name: SAMSUNG_NP1234567890 dmi.board.vendor: SAMSUNG ELECTRONICS CO., LTD. dmi.board.version: FAB1 dmi.chassis.asset.tag: No Asset Tag dmi.chassis.type: 9 dmi.chassis.vendor: SAMSUNG ELECTRONICS CO., LTD. dmi.chassis.version: 0.1 dmi.modalias: dmi:bvnPhoenixTechnologiesLtd.:bvrP04AAE:bd08/02/2012:svnSAMSUNGELECTRONICSCO.,LTD.:pn700Z7C:pvr0.1:rvnSAMSUNGELECTRONICSCO.,LTD.:rnSAMSUNG_NP1234567890:rvrFAB1:cvnSAMSUNGELECTRONICSCO.,LTD.:ct9:cvr0.1: dmi.product.name: 700Z7C dmi.product.version: 0.1 dmi.sys.vendor: SAMSUNG ELECTRONICS CO., LTD. --- ApportVersion: 2.20.9-0ubuntu7 Architecture: amd64 AudioDevicesInUse: USER PID ACCESS COMMAND /dev/snd/controlC0: mio 1568 F.... pulseaudio CurrentDesktop: Unity:Unity7:ubuntu DistroRelease: Ubuntu 18.04 HibernationDevice: RESUME=UUID=3f9af81f-77f0-4438-9a4b-6722de269cbb InstallationDate: Installed on 2018-05-09 (9 days ago) InstallationMedia: Ubuntu 18.04 LTS "Bionic Beaver" - Release amd64 (20180426) MachineType: SAMSUNG ELECTRONICS CO., LTD. 700Z7C Package: linux (not installed) ProcFB: 0 inteldrmfb ProcKernelCmdLine: BOOT_IMAGE=/vmlinuz-4.15.0-20-generic root=UUID=7c436149-ab84-40d0-919f-032364393f9b ro quiet splash video=VGA1:d nouveau.runpm=0 vt.handoff=1 ProcVersionSignature: Ubuntu 4.15.0-20.21-generic 4.15.17 RelatedPackageVersions: linux-restricted-modules-4.15.0-20-generic N/A linux-backports-modules-4.15.0-20-generic N/A linux-firmware 1.173 Tags: bionic Uname: Linux 4.15.0-20-generic x86_64 UpgradeStatus: No upgrade log present (probably fresh install) UserGroups: adm cdrom dip lp lpadmin plugdev sambashare sudo _MarkForUpload: True dmi.bios.date: 08/02/2012 dmi.bios.vendor: Phoenix Technologies Ltd. dmi.bios.version: P04AAE dmi.board.asset.tag: Base Board Asset Tag dmi.board.name: SAMSUNG_NP1234567890 dmi.board.vendor: SAMSUNG ELECTRONICS CO., LTD. dmi.board.version: FAB1 dmi.chassis.asset.tag: No Asset Tag dmi.chassis.type: 9 dmi.chassis.vendor: SAMSUNG ELECTRONICS CO., LTD. dmi.chassis.version: 0.1 dmi.modalias: dmi:bvnPhoenixTechnologiesLtd.:bvrP04AAE:bd08/02/2012:svnSAMSUNGELECTRONICSCO.,LTD.:pn700Z7C:pvr0.1:rvnSAMSUNGELECTRONICSCO.,LTD.:rnSAMSUNG_NP1234567890:rvrFAB1:cvnSAMSUNGELECTRONICSCO.,LTD.:ct9:cvr0.1: dmi.product.family: ChiefRiver System dmi.product.name: 700Z7C dmi.product.version: 0.1 dmi.sys.vendor: SAMSUNG ELECTRONICS CO., LTD. + --- + ApportVersion: 2.20.9-0ubuntu7 + Architecture: amd64 + AudioDevicesInUse: + USER PID ACCESS COMMAND + /dev/snd/controlC0: mio 1568 F.... pulseaudio + CurrentDesktop: Unity:Unity7:ubuntu + DistroRelease: Ubuntu 18.04 + HibernationDevice: RESUME=UUID=3f9af81f-77f0-4438-9a4b-6722de269cbb + InstallationDate: Installed on 2018-05-09 (9 days ago) + InstallationMedia: Ubuntu 18.04 LTS "Bionic Beaver" - Release amd64 (20180426) + MachineType: SAMSUNG ELECTRONICS CO., LTD. 700Z7C + Package: linux (not installed) + ProcFB: 0 inteldrmfb + ProcKernelCmdLine: BOOT_IMAGE=/vmlinuz-4.15.0-20-generic root=UUID=7c436149-ab84-40d0-919f-032364393f9b ro quiet splash video=VGA1:d nouveau.runpm=0 vt.handoff=1 + ProcVersionSignature: Ubuntu 4.15.0-20.21-generic 4.15.17 + RelatedPackageVersions: + linux-restricted-modules-4.15.0-20-generic N/A + linux-backports-modules-4.15.0-20-generic N/A + linux-firmware 1.173 + Tags: bionic + Uname: Linux 4.15.0-20-generic x86_64 + UpgradeStatus: No upgrade log present (probably fresh install) + UserGroups: adm cdrom dip lp lpadmin plugdev sambashare sudo + _MarkForUpload: True + dmi.bios.date: 08/02/2012 + dmi.bios.vendor: Phoenix Technologies Ltd. + dmi.bios.version: P04AAE + dmi.board.asset.tag: Base Board Asset Tag + dmi.board.name: SAMSUNG_NP1234567890 + dmi.board.vendor: SAMSUNG ELECTRONICS CO., LTD. + dmi.board.version: FAB1 + dmi.chassis.asset.tag: No Asset Tag + dmi.chassis.type: 9 + dmi.chassis.vendor: SAMSUNG ELECTRONICS CO., LTD. + dmi.chassis.version: 0.1 + dmi.modalias: dmi:bvnPhoenixTechnologiesLtd.:bvrP04AAE:bd08/02/2012:svnSAMSUNGELECTRONICSCO.,LTD.:pn700Z7C:pvr0.1:rvnSAMSUNGELECTRONICSCO.,LTD.:rnSAMSUNG_NP1234567890:rvrFAB1:cvnSAMSUNGELECTRONICSCO.,LTD.:ct9:cvr0.1: + dmi.product.family: ChiefRiver System + dmi.product.name: 700Z7C + dmi.product.version: 0.1 + dmi.sys.vendor: SAMSUNG ELECTRONICS CO., LTD. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1087010 Title: kworker uses 70-90% of a CPU core (hyperthreaded) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1087010/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
