From: bugzilla-daemon@bugzilla.kernel.org
To: cpufreq@vger.kernel.org
Subject: [Bug 48721] New: acpi_cpufreq can't change CPU clock anymore
Date: Sat, 13 Oct 2012 01:56:34 +0000 (UTC) [thread overview]
Message-ID: <bug-48721-12968@https.bugzilla.kernel.org/> (raw)
https://bugzilla.kernel.org/show_bug.cgi?id=48721
Summary: acpi_cpufreq can't change CPU clock anymore
Product: Power Management
Version: 2.5
Kernel Version: 3.6.1
Platform: All
OS/Version: Linux
Tree: Mainline
Status: NEW
Severity: normal
Priority: P1
Component: cpufreq
AssignedTo: cpufreq@vger.kernel.org
ReportedBy: mavoga@gmail.com
Regression: Yes
Created an attachment (id=83121)
--> (https://bugzilla.kernel.org/attachment.cgi?id=83121)
3.5.5 kernel: output of 'grep -r . /sys/devices/system/cpu/ 2>/dev/null'
On my laptop (a Clevo W150HRM with an i7 2720QM CPU) I'm currently running
Debian wheezy/sid with latest aptosid (3.6-1.slh.3) amd64 kernel: after
switching from 3.5.5 to 3.6 kernel I noticed the idle temperatures suddenly
increased by ~10°C with no apparent activity on the system.
The temperature increase, together with sysfs scaling_cur_freq and
cpuinfo_cur_freq values seem to support my suspect of a cpufreq bug: the
ondemand governor doesn't seem able to modulate the CPU clock anymore. While
the scaling_cur_freq value varies depending on system load just as expected,
the cpuinfo_cur_freq value remains stuck at (or over because of turbo boost)
the maximum CPU frequency, just like the performance governor was set.
I could get the same frequency readings with cpufreq-info, turbostat and i7z:
the CPU frequency never decreases under 2.2GHz.
Furthermore, no cpufreq-set setting seems able to lower the idle frequency in
any way, even by changing governor, and a test 3.6.1 vanilla kernel I compiled
for testing purposes showed the same behavior.
As soon as I reboot to a 3.5.5 kernel cpuinfo_cur_freq begin to follow
scaling_cur_freq just as expected, and the idle temps decrease back by over
10°C.
--
Configure bugmail: https://bugzilla.kernel.org/userprefs.cgi?tab=email
------- You are receiving this mail because: -------
You are the assignee for the bug.
next reply other threads:[~2012-10-13 1:56 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-10-13 1:56 bugzilla-daemon [this message]
2012-10-13 1:57 ` [Bug 48721] acpi_cpufreq can't change CPU clock anymore bugzilla-daemon
2012-10-13 2:03 ` bugzilla-daemon
2012-10-13 2:03 ` bugzilla-daemon
2012-10-13 2:08 ` bugzilla-daemon
2012-10-13 2:29 ` bugzilla-daemon
2012-10-13 7:17 ` bugzilla-daemon
2012-10-14 12:12 ` bugzilla-daemon
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=bug-48721-12968@https.bugzilla.kernel.org/ \
--to=bugzilla-daemon@bugzilla.kernel.org \
--cc=cpufreq@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).