cpuidle/coupled: Add sanity check for safe_state_index

Since we are using cpuidle_driver::safe_state_index directly as the
target state index, it is better to add the sanity check at the point
of registering the driver.

Signed-off-by: Xunlei Pang <pang.xunlei@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This commit is contained in:
Xunlei Pang 2015-08-31 11:34:05 +08:00 committed by Rafael J. Wysocki
parent 4c1ed5a607
commit abceaa9cde
3 changed files with 32 additions and 0 deletions

View File

@ -186,6 +186,28 @@ bool cpuidle_state_is_coupled(struct cpuidle_driver *drv, int state)
return drv->states[state].flags & CPUIDLE_FLAG_COUPLED; return drv->states[state].flags & CPUIDLE_FLAG_COUPLED;
} }
/**
* cpuidle_coupled_state_verify - check if the coupled states are correctly set.
* @drv: struct cpuidle_driver for the platform
*
* Returns 0 for valid state values, a negative error code otherwise:
* * -EINVAL if any coupled state(safe_state_index) is wrongly set.
*/
int cpuidle_coupled_state_verify(struct cpuidle_driver *drv)
{
int i;
for (i = drv->state_count - 1; i >= 0; i--) {
if (cpuidle_state_is_coupled(drv, i) &&
(drv->safe_state_index == i ||
drv->safe_state_index < 0 ||
drv->safe_state_index >= drv->state_count))
return -EINVAL;
}
return 0;
}
/** /**
* cpuidle_coupled_set_ready - mark a cpu as ready * cpuidle_coupled_set_ready - mark a cpu as ready
* @coupled: the struct coupled that contains the current cpu * @coupled: the struct coupled that contains the current cpu

View File

@ -35,6 +35,7 @@ extern void cpuidle_remove_sysfs(struct cpuidle_device *dev);
#ifdef CONFIG_ARCH_NEEDS_CPU_IDLE_COUPLED #ifdef CONFIG_ARCH_NEEDS_CPU_IDLE_COUPLED
bool cpuidle_state_is_coupled(struct cpuidle_driver *drv, int state); bool cpuidle_state_is_coupled(struct cpuidle_driver *drv, int state);
int cpuidle_coupled_state_verify(struct cpuidle_driver *drv);
int cpuidle_enter_state_coupled(struct cpuidle_device *dev, int cpuidle_enter_state_coupled(struct cpuidle_device *dev,
struct cpuidle_driver *drv, int next_state); struct cpuidle_driver *drv, int next_state);
int cpuidle_coupled_register_device(struct cpuidle_device *dev); int cpuidle_coupled_register_device(struct cpuidle_device *dev);
@ -46,6 +47,11 @@ bool cpuidle_state_is_coupled(struct cpuidle_driver *drv, int state)
return false; return false;
} }
static inline int cpuidle_coupled_state_verify(struct cpuidle_driver *drv)
{
return 0;
}
static inline int cpuidle_enter_state_coupled(struct cpuidle_device *dev, static inline int cpuidle_enter_state_coupled(struct cpuidle_device *dev,
struct cpuidle_driver *drv, int next_state) struct cpuidle_driver *drv, int next_state)
{ {

View File

@ -227,6 +227,10 @@ static int __cpuidle_register_driver(struct cpuidle_driver *drv)
if (!drv || !drv->state_count) if (!drv || !drv->state_count)
return -EINVAL; return -EINVAL;
ret = cpuidle_coupled_state_verify(drv);
if (ret)
return ret;
if (cpuidle_disabled()) if (cpuidle_disabled())
return -ENODEV; return -ENODEV;