cpuidle: fix fallback mechanism for suspend to idle in absence of enter_freeze
Commit 51164251f5c3 "sched / idle: Drop default_idle_call() fallback
from call_cpuidle()" made find_deepest_state() return non-negative
value and check all the states with index > 0. Also as a result,
find_deepest_state() returns 0 even when enter_freeze callbacks are not
implemented and enter_freeze_proper() is called which ends up crashing
the kernel.
This patch updates the check for index > 0 in cpuidle_enter_freeze and
cpuidle_idle_call(when idle_should_freeze is true) to restore the
suspend-to-idle functionality in absence of enter_freeze callback.
Fixes: 51164251f5c3 "sched / idle: Drop default_idle_call() fallback from call_cpuidle()"
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c
index 046423b..f996efc 100644
--- a/drivers/cpuidle/cpuidle.c
+++ b/drivers/cpuidle/cpuidle.c
@@ -153,7 +153,7 @@
* be frozen safely.
*/
index = find_deepest_state(drv, dev, UINT_MAX, 0, true);
- if (index >= 0)
+ if (index > 0)
enter_freeze_proper(drv, dev, index);
return index;
diff --git a/kernel/sched/idle.c b/kernel/sched/idle.c
index 34852ee..30f7b6a 100644
--- a/kernel/sched/idle.c
+++ b/kernel/sched/idle.c
@@ -162,7 +162,7 @@
*/
if (idle_should_freeze()) {
entered_state = cpuidle_enter_freeze(drv, dev);
- if (entered_state >= 0) {
+ if (entered_state > 0) {
local_irq_enable();
goto exit_idle;
}