Linux kernel -stable discussions
 help / color / mirror / Atom feed
From: Thomas Gleixner <tglx@linutronix.de>
To: Tejun Heo <tj@kernel.org>
Cc: LKML <linux-kernel@vger.kernel.org>,
	"Rafael J. Wysocki" <rjw@sisk.pl>,
	Andreas Herrmann <andreas.herrmann3@amd.com>,
	stable@vger.kernel.org, Carsten Emde <C.Emde@osadl.org>
Subject: Re: [PATCH] cpufreq: powernow-k8: Remove bogus smp_processor_id() usage
Date: Sat, 27 Oct 2012 21:19:39 +0200 (CEST)	[thread overview]
Message-ID: <alpine.LFD.2.02.1210272118590.2756@ionos> (raw)
In-Reply-To: <20121027191051.GA2693@htj.dyndns.org>

On Sat, 27 Oct 2012, Tejun Heo wrote:

> Hello, Thomas.
> 
> On Sat, Oct 27, 2012 at 07:29:25PM +0200, Thomas Gleixner wrote:
> > This is fully preemptible non cpu bound context though the comment in the
> > code says:
> > 
> > 	 * Must run on @pol->cpu.  cpufreq core is responsible for ensuring
> > 	 * that we're bound to the current CPU and pol->cpu stays online.
> > 
> > The core only guarantees that pol->cpu stays online, but it has no way
> > to bind the thread and this needs to be fully preemptible context as
> > powernowk8_target_fn() calls functions which might sleep.
> > 
> > So the correct solution is to always go through work_on_cpu().
> 
> Yeah, that was stupid.  Rafael already has a patch queued.
> 
>   http://git.kernel.org/?p=linux/kernel/git/rafael/linux-pm.git;a=commit;h=e4df1cbcc1f329e53a1fff7450b2229e0addff20
> 

Good. So more people noticed :)

      tglx

      reply	other threads:[~2012-10-27 19:19 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-10-27 17:29 [PATCH] cpufreq: powernow-k8: Remove bogus smp_processor_id() usage Thomas Gleixner
2012-10-27 19:10 ` Tejun Heo
2012-10-27 19:19   ` Thomas Gleixner [this message]

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=alpine.LFD.2.02.1210272118590.2756@ionos \
    --to=tglx@linutronix.de \
    --cc=C.Emde@osadl.org \
    --cc=andreas.herrmann3@amd.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=rjw@sisk.pl \
    --cc=stable@vger.kernel.org \
    --cc=tj@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