Re: stable 3-10-3: strange output of "lsmod | grep ^acpi_cpufreq"

["Rafael J. Wysocki" <rjw@sisk.pl>]

On Monday, July 29, 2013 12:11:18 AM Rafael J. Wysocki wrote:
> On Sunday, July 28, 2013 12:21:22 PM Toralf Förster wrote:
> > On 07/28/2013 01:39 AM, Rafael J. Wysocki wrote:
> > > On Saturday, July 27, 2013 07:40:34 PM Toralf Förster wrote:
> > >> it gives at a ThinkPad T420:
> > >>
> > >> tfoerste@n22 ~/tmp $ lsmod | grep ^acpi_cpufreq
> > >> acpi_cpufreq           12902  2147483647
> > > 
> > > That is -1, which indicates some module refcount woes.
> > 
> > yes, ofc.
> > 
> > The issue apears after 1 s2ram/resume cycle, before s2ram the refcount is 1.
> > 
> > > I definitely can't see that with the mainline on my machines.
> > 
> > It is in mainline too.
> 
> Does the appended patch help?

Actually, something as simple as this also should help:

---
From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Subject: cpufreq: Fix cpufreq driver module refcount balance after suspend/resume

Since cpufreq_cpu_put() called by __cpufreq_remove_dev() drops the
driver module refcount, __cpufreq_remove_dev() causes that refcount
to become negative after a suspend/resume cycle, for example.

To prevent this from happening make __cpufreq_remove_dev() put
the policy kobject only instead of calling cpufreq_cpu_put().

Reported-by: Toralf Förster <toralf.foerster@gmx.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
---
 drivers/cpufreq/cpufreq.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Index: linux-pm/drivers/cpufreq/cpufreq.c
===================================================================
--- linux-pm.orig/drivers/cpufreq/cpufreq.c
+++ linux-pm/drivers/cpufreq/cpufreq.c
@@ -1181,7 +1181,7 @@ static int __cpufreq_remove_dev(struct d
 		__cpufreq_governor(data, CPUFREQ_GOV_POLICY_EXIT);
 
 	pr_debug("%s: removing link, cpu: %d\n", __func__, cpu);
-	cpufreq_cpu_put(data);
+	kobject_put(&data->kobj);
 
 	/* If cpu is last user of policy, free policy */
 	if (cpus == 1) {