USB: cdc-acm: fix write and suspend race
[pandora-kernel.git] / drivers / usb / class / cdc-acm.c
index 320db2a..456ec17 100644 (file)
@@ -1338,18 +1338,15 @@ static int acm_suspend(struct usb_interface *intf, pm_message_t message)
        struct acm *acm = usb_get_intfdata(intf);
        int cnt;
 
+       spin_lock_irq(&acm->read_lock);
+       spin_lock(&acm->write_lock);
        if (PMSG_IS_AUTO(message)) {
-               int b;
-
-               spin_lock_irq(&acm->write_lock);
-               b = acm->transmitting;
-               spin_unlock_irq(&acm->write_lock);
-               if (b)
+               if (acm->transmitting) {
+                       spin_unlock(&acm->write_lock);
+                       spin_unlock_irq(&acm->read_lock);
                        return -EBUSY;
+               }
        }
-
-       spin_lock_irq(&acm->read_lock);
-       spin_lock(&acm->write_lock);
        cnt = acm->susp_count++;
        spin_unlock(&acm->write_lock);
        spin_unlock_irq(&acm->read_lock);