HID: sensor-hub: make dyn_callback_lock IRQ-safe

dyn_callback_lock is being taken from IRQ context through hid_irq_in() ->
hid_input_report() -> sensor_hub_raw_event() -> sensor_hub_get_callback(),
therefore anyone else acquiring it needs to disable IRQs to disable deadlocks.

Reported-by: Alexander Holler <holler@ahsoftware.de>
Tested-by: Alexander Holler <holler@ahsoftware.de>
Reported-by: Reyad Attiyat <reyad.attiyat@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

diff --git a/drivers/hid/hid-sensor-hub.c b/drivers/hid/hid-sensor-hub.c
index a8d5c8f..13ce4e3 100644 (file)
--- a/drivers/hid/hid-sensor-hub.c
+++ b/drivers/hid/hid-sensor-hub.c
@@ -159,17 +159,18 @@ int sensor_hub_register_callback(struct hid_sensor_hub_device *hsdev,
 {
        struct hid_sensor_hub_callbacks_list *callback;
        struct sensor_hub_data *pdata = hid_get_drvdata(hsdev->hdev);
+       unsigned long flags;
 
-       spin_lock(&pdata->dyn_callback_lock);
+       spin_lock_irqsave(&pdata->dyn_callback_lock, flags);
        list_for_each_entry(callback, &pdata->dyn_callback_list, list)
                if (callback->usage_id == usage_id &&
                                                callback->hsdev == hsdev) {
-                       spin_unlock(&pdata->dyn_callback_lock);
+                       spin_unlock_irqrestore(&pdata->dyn_callback_lock, flags);
                        return -EINVAL;
                }
        callback = kzalloc(sizeof(*callback), GFP_ATOMIC);
        if (!callback) {
-               spin_unlock(&pdata->dyn_callback_lock);
+               spin_unlock_irqrestore(&pdata->dyn_callback_lock, flags);
                return -ENOMEM;
        }
        callback->hsdev = hsdev;
@@ -177,7 +178,7 @@ int sensor_hub_register_callback(struct hid_sensor_hub_device *hsdev,
        callback->usage_id = usage_id;
        callback->priv = NULL;
        list_add_tail(&callback->list, &pdata->dyn_callback_list);
-       spin_unlock(&pdata->dyn_callback_lock);
+       spin_unlock_irqrestore(&pdata->dyn_callback_lock, flags);
 
        return 0;
 }
@@ -188,8 +189,9 @@ int sensor_hub_remove_callback(struct hid_sensor_hub_device *hsdev,
 {
        struct hid_sensor_hub_callbacks_list *callback;
        struct sensor_hub_data *pdata = hid_get_drvdata(hsdev->hdev);
+       unsigned long flags;
 
-       spin_lock(&pdata->dyn_callback_lock);
+       spin_lock_irqsave(&pdata->dyn_callback_lock, flags);
        list_for_each_entry(callback, &pdata->dyn_callback_list, list)
                if (callback->usage_id == usage_id &&
                                                callback->hsdev == hsdev) {
@@ -197,7 +199,7 @@ int sensor_hub_remove_callback(struct hid_sensor_hub_device *hsdev,
                        kfree(callback);
                        break;
                }
-       spin_unlock(&pdata->dyn_callback_lock);
+       spin_unlock_irqrestore(&pdata->dyn_callback_lock, flags);
 
        return 0;
 }
@@ -378,15 +380,16 @@ static int sensor_hub_suspend(struct hid_device *hdev, pm_message_t message)
 {
        struct sensor_hub_data *pdata = hid_get_drvdata(hdev);
        struct hid_sensor_hub_callbacks_list *callback;
+       unsigned long flags;
 
        hid_dbg(hdev, " sensor_hub_suspend\n");
-       spin_lock(&pdata->dyn_callback_lock);
+       spin_lock_irqsave(&pdata->dyn_callback_lock, flags);
        list_for_each_entry(callback, &pdata->dyn_callback_list, list) {
                if (callback->usage_callback->suspend)
                        callback->usage_callback->suspend(
                                        callback->hsdev, callback->priv);
        }
-       spin_unlock(&pdata->dyn_callback_lock);
+       spin_unlock_irqrestore(&pdata->dyn_callback_lock, flags);
 
        return 0;
 }
@@ -395,15 +398,16 @@ static int sensor_hub_resume(struct hid_device *hdev)
 {
        struct sensor_hub_data *pdata = hid_get_drvdata(hdev);
        struct hid_sensor_hub_callbacks_list *callback;
+       unsigned long flags;
 
        hid_dbg(hdev, " sensor_hub_resume\n");
-       spin_lock(&pdata->dyn_callback_lock);
+       spin_lock_irqsave(&pdata->dyn_callback_lock, flags);
        list_for_each_entry(callback, &pdata->dyn_callback_list, list) {
                if (callback->usage_callback->resume)
                        callback->usage_callback->resume(
                                        callback->hsdev, callback->priv);
        }
-       spin_unlock(&pdata->dyn_callback_lock);
+       spin_unlock_irqrestore(&pdata->dyn_callback_lock, flags);
 
        return 0;
 }