From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Doug Smythies" Subject: RE: PROBLEM: Cpufreq constantly keeps frequency at maximum on 4.5-rc4 Date: Sat, 20 Feb 2016 08:31:18 -0800 Message-ID: <000401d16bfc$21338450$639a8cf0$@net> References: <87egc7ahqn.fsf@iki.fi> Mime-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit Return-path: Received: from cmta6.telus.net ([209.171.16.79]:50440 "EHLO cmta6.telus.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757548AbcBTQbW (ORCPT ); Sat, 20 Feb 2016 11:31:22 -0500 In-Reply-To: <87egc7ahqn.fsf@iki.fi> Content-Language: en-ca Sender: linux-pm-owner@vger.kernel.org List-Id: linux-pm@vger.kernel.org To: 'Arto Jantunen' Cc: "'Rafael J. Wysocki'" , 'Viresh Kumar' , linux-pm@vger.kernel.org, 'Srinivas Pandruvada' On 2106.02.20 00:50 Arto Jantunen wrote: > When using kernel 4.5-rc4 my Skylake machine runs very warm since all > cpu cores are always kept at 3.10Ghz (with maximum without turboboost > being 2.6Ghz), completely regardless of load. Swapping between the > governors (performance and powersave) doesn't change the result in any > way, frequency remains at a constant 3.10Ghz. > > The machine is using the intel_pstate driver, I don't know if it's > possible to choose to use the acpi driver instead (without recompiling > the kernel so that intel_pstate is not supported). If you use grub then you can disable the intel_pstate driver by modifying the grub command line. Here is an example, where I have left other stuff that I use: GRUB_CMDLINE_LINUX_DEFAULT="ipv6.disable=1 intel_pstate=disable net.ifnames=1 biosdevname=0" Here is an example, with the intel_pstate directive by itself: GRUB_CMDLINE_LINUX_DEFAULT="intel_pstate=disable" If the intel_pstate driver is disabled, then the acpi-cpufreq CPU frequency scaling driver will be used. Remember to update grub after the above edit. If you do not use grub, then I don't know. Please, and as a test, also try this and report back: GRUB_CMDLINE_LINUX_DEFAULT="intel_pstate=no_hwp" > I can force the frequency down manually with cpufreq-set, so the problem > doesn't seem to be with the actual frequency changing. > Cpuinfo (taken from 4.4 which doesn't have the problem): Is kernel 4.5-rc4 the first one you have tried in the 4.5 series? What I am asking is if you know if the issue was introduced between kernels 4.4 and 4.5-rc1 (most likely) or between 4.5-rc3 and 4.5-rc4 or? What distribution, if any, of Linux do you use? It might make sense to take this off-list and into a bugzilla bug report. ... Doug