Merge tag 'pm-7.0-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull power management fixes from Rafael Wysocki:
 "These fix an idle loop issue exposed by recent changes and a race
  condition related to device removal in the runtime PM core code:

   - Consolidate the handling of two special cases in the idle loop that
     occur when only one CPU idle state is present (Rafael Wysocki)

   - Fix a race condition related to device removal in the runtime PM
     core code that may cause a stale device object pointer to be
     dereferenced (Bart Van Assche)"

* tag 'pm-7.0-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  PM: runtime: Fix a race condition related to device removal
  sched: idle: Consolidate the handling of two special cases
This commit is contained in:
Linus Torvalds
2026-03-19 08:45:34 -07:00
2 changed files with 22 additions and 9 deletions

View File

@@ -1895,6 +1895,7 @@ void pm_runtime_reinit(struct device *dev)
void pm_runtime_remove(struct device *dev)
{
__pm_runtime_disable(dev, false);
flush_work(&dev->power.work);
pm_runtime_reinit(dev);
}

View File

@@ -161,6 +161,14 @@ static int call_cpuidle(struct cpuidle_driver *drv, struct cpuidle_device *dev,
return cpuidle_enter(drv, dev, next_state);
}
static void idle_call_stop_or_retain_tick(bool stop_tick)
{
if (stop_tick || tick_nohz_tick_stopped())
tick_nohz_idle_stop_tick();
else
tick_nohz_idle_retain_tick();
}
/**
* cpuidle_idle_call - the main idle function
*
@@ -170,7 +178,7 @@ static int call_cpuidle(struct cpuidle_driver *drv, struct cpuidle_device *dev,
* set, and it returns with polling set. If it ever stops polling, it
* must clear the polling bit.
*/
static void cpuidle_idle_call(void)
static void cpuidle_idle_call(bool stop_tick)
{
struct cpuidle_device *dev = cpuidle_get_device();
struct cpuidle_driver *drv = cpuidle_get_cpu_driver(dev);
@@ -186,7 +194,7 @@ static void cpuidle_idle_call(void)
}
if (cpuidle_not_available(drv, dev)) {
tick_nohz_idle_stop_tick();
idle_call_stop_or_retain_tick(stop_tick);
default_idle_call();
goto exit_idle;
@@ -222,17 +230,19 @@ static void cpuidle_idle_call(void)
next_state = cpuidle_find_deepest_state(drv, dev, max_latency_ns);
call_cpuidle(drv, dev, next_state);
} else if (drv->state_count > 1) {
bool stop_tick = true;
/*
* stop_tick is expected to be true by default by cpuidle
* governors, which allows them to select idle states with
* target residency above the tick period length.
*/
stop_tick = true;
/*
* Ask the cpuidle framework to choose a convenient idle state.
*/
next_state = cpuidle_select(drv, dev, &stop_tick);
if (stop_tick || tick_nohz_tick_stopped())
tick_nohz_idle_stop_tick();
else
tick_nohz_idle_retain_tick();
idle_call_stop_or_retain_tick(stop_tick);
entered_state = call_cpuidle(drv, dev, next_state);
/*
@@ -240,7 +250,7 @@ static void cpuidle_idle_call(void)
*/
cpuidle_reflect(dev, entered_state);
} else {
tick_nohz_idle_retain_tick();
idle_call_stop_or_retain_tick(stop_tick);
/*
* If there is only a single idle state (or none), there is
@@ -268,6 +278,7 @@ exit_idle:
static void do_idle(void)
{
int cpu = smp_processor_id();
bool got_tick = false;
/*
* Check if we need to update blocked load
@@ -338,8 +349,9 @@ static void do_idle(void)
tick_nohz_idle_restart_tick();
cpu_idle_poll();
} else {
cpuidle_idle_call();
cpuidle_idle_call(got_tick);
}
got_tick = tick_nohz_idle_got_tick();
arch_cpu_idle_exit();
}