[PATCH 2/4] cpuidle: Check the sign of index in cpuidle_reflect()

Rafael J. Wysocki
2015-05-04T13:35:08Z

From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Avoid calling the governor's ->reflect method if the state index
passed to cpuidle_reflect() is negative.

This allows the analogous check to be dropped from menu_reflect(),
so do that too, and ensures that arbitrary error codes can be
passed to cpuidle_reflect() as the index with no adverse
consequences.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
---
drivers/cpuidle/cpuidle.c | 2 +-
drivers/cpuidle/governors/menu.c | 4 ++--
2 files changed, 3 insertions(+), 3 deletions(-)

Index: linux-pm/drivers/cpuidle/cpuidle.c
===================================================================
--- linux-pm.orig/drivers/cpuidle/cpuidle.c
+++ linux-pm/drivers/cpuidle/cpuidle.c
@@ -249,7 +249,7 @@ int cpuidle_enter(struct cpuidle_driver
*/
void cpuidle_reflect(struct cpuidle_device *dev, int index)
{
- if (cpuidle_curr_governor->reflect)
+ if (cpuidle_curr_governor->reflect && index >= 0)
cpuidle_curr_governor->reflect(dev, index);
}

Index: linux-pm/drivers/cpuidle/governors/menu.c
===================================================================
--- linux-pm.orig/drivers/cpuidle/governors/menu.c
+++ linux-pm/drivers/cpuidle/governors/menu.c
@@ -367,9 +367,9 @@ static int menu_select(struct cpuidle_dr
static void menu_reflect(struct cpuidle_device *dev, int index)
{
struct menu_device *data = this_cpu_ptr(&menu_devices);
+
data->last_state_idx = index;
- if (index >= 0)
- data->needs_update = 1;
+ data->needs_update = 1;
}

/**