I'm not enormously keen to upgrade the BIOS, given that this is a regression with a relatively easy workaround, that BIOS updates can be risky, and that Dell lists the only change as "Fix system resume from S4 automatically after upgrade to Windows 8", but I'll see what I can do.
-- 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/1233479 Title: [Dell XPS 15 L502X] On demand cpufreq governor does not scale CPU freq Status in “linux” package in Ubuntu: Incomplete Bug description: I notice that turbostat shows all cpus stuck at the minimum 800MHz (see attached log) on my system, even after rebooting twice. I used "stress --cpu 8" to confirm that the frequencies remained at 800MHz even under load. It looks like the system is using the acpi-cpufreq driver with the ondemand governor (has the default been changed so it does not use intel p-state, as per https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1188647?). Edit: See comment #1 below - it looks like I can manually change the cpu freq, but the governor cannot. Also, switching to use intel pstate fixes the problem. The only unusual thing I had done prior to this was to boot into the weekly build of 3.12-rc3 just prior (this kernel kept the frequencies rather high, typically over 2GHz, ie using a lot more power than usual, so I rebooted back into the standard kernel). This is the contents of the files in /sys/devices/system/cpu/cpu0/cpufreq/: affected_cpus: 0 bios_limit: 2001000 cpuinfo_cur_freq: 800000 cpuinfo_max_freq: 2001000 cpuinfo_min_freq: 800000 cpuinfo_transition_latency: 10000 freqdomain_cpus: 0 1 2 3 4 5 6 7 related_cpus: 0 scaling_available_frequencies: 2001000 2000000 1900000 1800000 1700000 1600000 1500000 1400000 1300000 1200000 1100000 1000000 900000 800000 scaling_available_governors: conservative ondemand userspace powersave performance scaling_cur_freq: 800000 scaling_driver: acpi-cpufreq scaling_governor: ondemand scaling_max_freq: 2001000 scaling_min_freq: 800000 scaling_setspeed: <unsupported> stats: ProblemType: Bug DistroRelease: Ubuntu 13.10 Package: linux-image-3.11.0-9-generic 3.11.0-9.16 ProcVersionSignature: Ubuntu 3.11.0-9.16-generic 3.11.2 Uname: Linux 3.11.0-9-generic x86_64 ApportVersion: 2.12.5-0ubuntu1 Architecture: amd64 AudioDevicesInUse: USER PID ACCESS COMMAND /dev/snd/controlC0: rocko 2813 F.... pulseaudio Date: Tue Oct 1 10:13:24 2013 InstallationDate: Installed on 2012-08-25 (401 days ago) InstallationMedia: Ubuntu 12.10 "Quantal Quetzal" - Alpha amd64 (20120724.2) MachineType: Dell Inc. Dell System XPS L502X MarkForUpload: True ProcFB: 0 inteldrmfb ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.11.0-9-generic root=UUID=67083065-b92e-4596-a218-817c1dfc8ae7 ro crashkernel=384M-2G:64M,2G-:128M quiet splash vt.handoff=7 RelatedPackageVersions: linux-restricted-modules-3.11.0-9-generic N/A linux-backports-modules-3.11.0-9-generic N/A linux-firmware 1.115 SourcePackage: linux UpgradeStatus: Upgraded to saucy on 2013-09-01 (30 days ago) dmi.bios.date: 05/29/2012 dmi.bios.vendor: Dell Inc. dmi.bios.version: A11 dmi.board.name: 0NJT03 dmi.board.vendor: Dell Inc. dmi.board.version: A00 dmi.chassis.type: 8 dmi.chassis.vendor: Dell Inc. dmi.chassis.version: 0.1 dmi.modalias: dmi:bvnDellInc.:bvrA11:bd05/29/2012:svnDellInc.:pnDellSystemXPSL502X:pvr:rvnDellInc.:rn0NJT03:rvrA00:cvnDellInc.:ct8:cvr0.1: dmi.product.name: Dell System XPS L502X dmi.sys.vendor: Dell Inc. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1233479/+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