linux-pm.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: bugzilla-daemon@bugzilla.kernel.org
To: linux-pm@kernel.org
Subject: [Bug 198637] New: cpuinfo_cur_freq differs from scaling_cur_freq on an AMD FX-8320E
Date: Thu, 01 Feb 2018 17:17:41 +0000	[thread overview]
Message-ID: <bug-198637-137361@https.bugzilla.kernel.org/> (raw)

https://bugzilla.kernel.org/show_bug.cgi?id=198637

            Bug ID: 198637
           Summary: cpuinfo_cur_freq differs from scaling_cur_freq on an
                    AMD FX-8320E
           Product: Power Management
           Version: 2.5
    Kernel Version: 4.15.0
          Hardware: x86-64
                OS: Linux
              Tree: Mainline
            Status: NEW
          Severity: normal
          Priority: P1
         Component: cpufreq
          Assignee: linux-pm@vger.kernel.org
          Reporter: stefantalpalaru@yahoo.com
        Regression: No

With the "performance" governor:

root# cat /sys/devices/system/cpu/cpu*/cpufreq/cpuinfo_cur_freq
4400000
4400000
4400000
4400000
4400000
4400000
4400000
4400000
root# cat /sys/devices/system/cpu/cpu*/cpufreq/scaling_cur_freq 
3029755
3114686
4173759
4365672
2865808
3887821
4247518
3671205

This is a problem because only the latter, wrong value is readable by non-root
users and it's also the only one shown in /proc/cpuinfo.

According to this 2011 email -
http://permalink.gmane.org/gmane.linux.kernel.cpufreq/7008 :

> everyone may read out scaling_cur_freq, and scaling_cur_freq differs from
cpuinfo_cur_freq _only_ if something is broken

So what's broken and how can we fix it?

Additional info:
- scaling_driver is "acpi-cpufreq"
- scaling_min_freq and scaling_max_freq have correct values (same as their
cpuinfo_ counterparts)
- the CPU has Turbo Core disabled and it's overclocked to 4.4GHz but the
problem should also manifest on default setups

-- 
You are receiving this mail because:
You are the assignee for the bug.

                 reply	other threads:[~2018-02-01 17:17 UTC|newest]

Thread overview: [no followups] expand[flat|nested]  mbox.gz  Atom feed

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-198637-137361@https.bugzilla.kernel.org/ \
    --to=bugzilla-daemon@bugzilla.kernel.org \
    --cc=linux-pm@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).