net: usb: kaweth: use irqsave() in USB's complete callback
authorSebastian Andrzej Siewior <bigeasy@linutronix.de>
Wed, 20 Jun 2018 19:31:19 +0000 (21:31 +0200)
committerDavid S. Miller <davem@davemloft.net>
Fri, 22 Jun 2018 04:57:45 +0000 (13:57 +0900)
The USB completion callback does not disable interrupts while acquiring
the lock. We want to remove the local_irq_disable() invocation from
__usb_hcd_giveback_urb() and therefore it is required for the callback
handler to disable the interrupts while acquiring the lock.
The callback may be invoked either in IRQ or BH context depending on the
USB host controller.
Use the _irqsave() variant of the locking primitives.

Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
drivers/net/usb/kaweth.c

index f1605833c5cf1d7eebe5f7189f0c4e43ba32e5ad..913e50bab0a2f6c039e30f8defe434284f5a487f 100644 (file)
@@ -587,7 +587,7 @@ static void kaweth_usb_receive(struct urb *urb)
        struct kaweth_device *kaweth = urb->context;
        struct net_device *net = kaweth->net;
        int status = urb->status;
-
+       unsigned long flags;
        int count = urb->actual_length;
        int count2 = urb->transfer_buffer_length;
 
@@ -619,12 +619,12 @@ static void kaweth_usb_receive(struct urb *urb)
                net->stats.rx_errors++;
                dev_dbg(dev, "Status was -EOVERFLOW.\n");
        }
-       spin_lock(&kaweth->device_lock);
+       spin_lock_irqsave(&kaweth->device_lock, flags);
        if (IS_BLOCKED(kaweth->status)) {
-               spin_unlock(&kaweth->device_lock);
+               spin_unlock_irqrestore(&kaweth->device_lock, flags);
                return;
        }
-       spin_unlock(&kaweth->device_lock);
+       spin_unlock_irqrestore(&kaweth->device_lock, flags);
 
        if(status && status != -EREMOTEIO && count != 1) {
                dev_err(&kaweth->intf->dev,