cpuidle: coupled: fix sleeping while atomic in cpu notifier
The cpu hotplug notifier gets called in both atomic and non-atomic
contexts, it is not always safe to lock a mutex. Filter out all events
except the six necessary ones, which are all sleepable, before taking
the mutex.
Signed-off-by: Colin Cross <ccross@android.com>
Reviewed-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
diff --git a/drivers/cpuidle/coupled.c b/drivers/cpuidle/coupled.c
index 2c9bf26..c24dda0 100644
--- a/drivers/cpuidle/coupled.c
+++ b/drivers/cpuidle/coupled.c
@@ -678,6 +678,18 @@
int cpu = (unsigned long)hcpu;
struct cpuidle_device *dev;
+ switch (action & ~CPU_TASKS_FROZEN) {
+ case CPU_UP_PREPARE:
+ case CPU_DOWN_PREPARE:
+ case CPU_ONLINE:
+ case CPU_DEAD:
+ case CPU_UP_CANCELED:
+ case CPU_DOWN_FAILED:
+ break;
+ default:
+ return NOTIFY_OK;
+ }
+
mutex_lock(&cpuidle_lock);
dev = per_cpu(cpuidle_devices, cpu);