The newest upstream kernel has the same bug. The symptoms in that upstream bug are identical (I also got this after an update to Yosemite) so this is almost certainly the same.
-- 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/1403653 Title: Kworker takes 100% CPU when booting with efi Status in The Linux Kernel: Unknown Status in linux package in Ubuntu: Triaged Bug description: When running on a Macbook Pro Retina that has been booted with EFI, a kworker process constantly takes 100% CPU. If you boot in legacy mode this does not happen. When grepping for large values in /sys/firmware/acpi/interrupts, this one stands out: /sys/firmware/acpi/interrupts/gpe66: 2510732 enabled Trying to disable it with echo disable > /sys/firmware/acpi/interrupts/gpe66 makes the CPU load go away. This will also prevent installation of Ubuntu, because if you try to install when kworker is running causes ubiquity to hang while trying to format the disk. ProblemType: Bug DistroRelease: Ubuntu 14.10 Package: linux-image-3.16.0-28-generic 3.16.0-28.38 ProcVersionSignature: Ubuntu 3.16.0-28.38-generic 3.16.7-ckt1 Uname: Linux 3.16.0-28-generic x86_64 ApportVersion: 2.14.7-0ubuntu8 Architecture: amd64 AudioDevicesInUse: USER PID ACCESS COMMAND /dev/snd/controlC1: jpakkane 2346 F.... pulseaudio /dev/snd/controlC0: jpakkane 2346 F.... pulseaudio CurrentDesktop: Unity Date: Wed Dec 17 23:36:32 2014 EcryptfsInUse: Yes InstallationDate: Installed on 2014-12-17 (0 days ago) InstallationMedia: Ubuntu 14.10 "Utopic Unicorn" - Release amd64 (20141022.1) MachineType: Apple Inc. MacBookPro11,1 ProcFB: 0 inteldrmfb ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.16.0-28-generic.efi.signed root=UUID=7196f220-ff77-4982-bfc1-03506a8013f7 ro quiet splash vt.handoff=7 RelatedPackageVersions: linux-restricted-modules-3.16.0-28-generic N/A linux-backports-modules-3.16.0-28-generic N/A linux-firmware 1.138 SourcePackage: linux UpgradeStatus: No upgrade log present (probably fresh install) dmi.bios.date: 08/29/2014 dmi.bios.vendor: Apple Inc. dmi.bios.version: MBP111.88Z.0138.B11.1408291433 dmi.board.asset.tag: Base Board Asset Tag# dmi.board.name: Mac-189A3D4F975D5FFC dmi.board.vendor: Apple Inc. dmi.board.version: MacBookPro11,1 dmi.chassis.type: 10 dmi.chassis.vendor: Apple Inc. dmi.chassis.version: Mac-189A3D4F975D5FFC dmi.modalias: dmi:bvnAppleInc.:bvrMBP111.88Z.0138.B11.1408291433:bd08/29/2014:svnAppleInc.:pnMacBookPro11,1:pvr1.0:rvnAppleInc.:rnMac-189A3D4F975D5FFC:rvrMacBookPro11,1:cvnAppleInc.:ct10:cvrMac-189A3D4F975D5FFC: dmi.product.name: MacBookPro11,1 dmi.product.version: 1.0 dmi.sys.vendor: Apple Inc. To manage notifications about this bug go to: https://bugs.launchpad.net/linux/+bug/1403653/+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
