From: John Ogness Date: Sat, 23 Jun 2018 22:32:13 +0000 (+0200) Subject: USB: serial: symbolserial: use irqsave() in USB's complete callback X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=5e02bfcf3f4f8c76c47718063d408c8a09d61bca;p=linux.git USB: serial: symbolserial: use irqsave() in USB's complete callback 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. Signed-off-by: John Ogness Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Johan Hovold --- diff --git a/drivers/usb/serial/symbolserial.c b/drivers/usb/serial/symbolserial.c index cd2f8dc8b58c6..6ca24e86f6869 100644 --- a/drivers/usb/serial/symbolserial.c +++ b/drivers/usb/serial/symbolserial.c @@ -35,6 +35,7 @@ static void symbol_int_callback(struct urb *urb) struct symbol_private *priv = usb_get_serial_port_data(port); unsigned char *data = urb->transfer_buffer; int status = urb->status; + unsigned long flags; int result; int data_length; @@ -73,7 +74,7 @@ static void symbol_int_callback(struct urb *urb) } exit: - spin_lock(&priv->lock); + spin_lock_irqsave(&priv->lock, flags); /* Continue trying to always read if we should */ if (!priv->throttled) { @@ -84,7 +85,7 @@ exit: __func__, result); } else priv->actually_throttled = true; - spin_unlock(&priv->lock); + spin_unlock_irqrestore(&priv->lock, flags); } static int symbol_open(struct tty_struct *tty, struct usb_serial_port *port)