We can perform a "Reverse" kernel bisect to identify the commit that fixes this bug in mainline. We first need to identify the last kernel version that had the bug and the first kernel that did no.
Can you test the following two kernels: v4.14-rc1: http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.14-rc1/ v4.15-rc1: http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.15-rc1/ ** Changed in: linux (Ubuntu) Importance: Undecided => Medium ** Changed in: linux (Ubuntu) Status: Confirmed => Triaged ** Tags added: needs-bisect -- 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/1743269 Title: P-state not working in kernel 4.13 Status in linux package in Ubuntu: Triaged Bug description: I have a Lenovo Thinkpad X230 with an Intel Core i5-3210M CPU. I'm using Xubuntu 17.10 (Description: Ubuntu 17.10, Release: 17.10). I use tlp 1.0-1~artful in order to improve battery performance, particularly enabling the Intel P-state performance scaling. In Xubuntu 17.04 it worked flawlessly, but when I upgraded to 17.10 the processor doesn't scale anymore. I ran all the updates and it's not working. I also did a clean install using another hard drive and the problem persist. I searched the tlp forums and similar problems pointed to a kernel bug, so I'm filing this report. I tested different mainline kernels in order to see what kernel version is causing the problem: Up to mainline kernel 4.12.14 generic, P-state scaling is OK Kernel 4.13 generic up to kernel 4.14.12 generic, P-state scaling is not working Kernel 4.14.13 generic up to 4.15 rc7 generic, P-state scaling is OK ProblemType: Bug DistroRelease: Ubuntu 17.10 Package: linux-image-4.13.0-25-generic 4.13.0-25.29 ProcVersionSignature: Ubuntu 4.13.0-25.29-generic 4.13.13 Uname: Linux 4.13.0-25-generic x86_64 ApportVersion: 2.20.7-0ubuntu3.7 Architecture: amd64 AudioDevicesInUse: USER PID ACCESS COMMAND /dev/snd/controlC0: eduar 1686 F.... pulseaudio CurrentDesktop: XFCE Date: Sun Jan 14 18:46:27 2018 HibernationDevice: RESUME=UUID=ec172c41-ddb8-4d67-8249-390aa1bb6331 InstallationDate: Installed on 2017-02-07 (341 days ago) InstallationMedia: Xubuntu 16.04.1 LTS "Xenial Xerus" - Release amd64 (20160719) MachineType: LENOVO 232032U ProcFB: 0 inteldrmfb ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.13.0-25-generic root=UUID=a5c459a3-f6c9-40cd-a648-e7b8b28a2ee6 ro radeon.dpm=1 quiet splash vt.handoff=7 RelatedPackageVersions: linux-restricted-modules-4.13.0-25-generic N/A linux-backports-modules-4.13.0-25-generic N/A linux-firmware 1.169.1 SourcePackage: linux UpgradeStatus: Upgraded to artful on 2018-01-13 (1 days ago) dmi.bios.date: 09/25/2017 dmi.bios.vendor: LENOVO dmi.bios.version: G2ETB0WW (2.70 ) dmi.board.asset.tag: Not Available dmi.board.name: 232032U dmi.board.vendor: LENOVO dmi.board.version: NO DPK dmi.chassis.asset.tag: No Asset Information dmi.chassis.type: 10 dmi.chassis.vendor: LENOVO dmi.chassis.version: Not Available dmi.modalias: dmi:bvnLENOVO:bvrG2ETB0WW(2.70):bd09/25/2017:svnLENOVO:pn232032U:pvrThinkPadX230:rvnLENOVO:rn232032U:rvrNODPK:cvnLENOVO:ct10:cvrNotAvailable: dmi.product.family: ThinkPad X230 dmi.product.name: 232032U dmi.product.version: ThinkPad X230 dmi.sys.vendor: LENOVO To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1743269/+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