Merge tag 'pm-5.0' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

torvalds · torvalds · commit ef4edb3ed830 · 2019-02-22T17:46:30.000-08:00
Pull power management fixes from Rafael Wysocki:
 "These fix a regression in the PM-runtime framework introduced by the
  recent switch-over of it to using hrtimers and a use-after-free
  introduced by one of the recent changes in the scmi-cpufreq driver.

  Specifics:

   - Use hrtimer_try_to_cancel() instead of hrtimer_cancel() in the
     PM-runtime framework to avoid a possible timer-related deadlock
     introduced recently (Vincent Guittot).

   - Reorder the scmi-cpufreq driver code to avoid accessing memory that
     has just been freed (Yangtao Li)"

* tag 'pm-5.0' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  PM-runtime: Fix deadlock when canceling hrtimer
  cpufreq: scmi: Fix use-after-free in scmi_cpufreq_exit()
diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c
@@ -95,7 +95,7 @@ static void __update_runtime_status(struct device *dev, enum rpm_status status)
 static void pm_runtime_deactivate_timer(struct device *dev)
 {
 	if (dev->power.timer_expires > 0) {
-		hrtimer_cancel(&dev->power.suspend_timer);
+		hrtimer_try_to_cancel(&dev->power.suspend_timer);
 		dev->power.timer_expires = 0;
 	}
 }
diff --git a/drivers/cpufreq/scmi-cpufreq.c b/drivers/cpufreq/scmi-cpufreq.c
@@ -187,8 +187,8 @@ static int scmi_cpufreq_exit(struct cpufreq_policy *policy)
 
 	cpufreq_cooling_unregister(priv->cdev);
 	dev_pm_opp_free_cpufreq_table(priv->cpu_dev, &policy->freq_table);
-	kfree(priv);
 	dev_pm_opp_remove_all_dynamic(priv->cpu_dev);
+	kfree(priv);
 
 	return 0;
 }

Original file line number	Diff line number	Diff line change
`@@ -95,7 +95,7 @@ static void __update_runtime_status(struct device *dev, enum rpm_status status)`
`95`	`95`	`static void pm_runtime_deactivate_timer(struct device *dev)`
`96`	`96`	`{`
`97`	`97`	`if (dev->power.timer_expires > 0) {`
`98`		`- hrtimer_cancel(&dev->power.suspend_timer);`
	`98`	`+ hrtimer_try_to_cancel(&dev->power.suspend_timer);`
`99`	`99`	`dev->power.timer_expires = 0;`
`100`	`100`	`}`
`101`	`101`	`}`
Original file line number	Diff line number	Diff line change
`@@ -187,8 +187,8 @@ static int scmi_cpufreq_exit(struct cpufreq_policy *policy)`
`187`	`187`
`188`	`188`	`cpufreq_cooling_unregister(priv->cdev);`
`189`	`189`	`dev_pm_opp_free_cpufreq_table(priv->cpu_dev, &policy->freq_table);`
`190`		`- kfree(priv);`
`191`	`190`	`dev_pm_opp_remove_all_dynamic(priv->cpu_dev);`
	`191`	`+ kfree(priv);`
`192`	`192`
`193`	`193`	`return 0;`
`194`	`194`	`}`