USB: serial: fix assumption that throttle/unthrottle cannot sleep
many serial subdrivers are clearly written as if throttle/unthrottle
cannot sleep. This leads to unneeded atomic submissions. This
patch converts affected drivers in a way to makes very clear that
throttle/unthrottle can sleep. Thus future misdesigns can be avoided
and efficiency and reliability improved.
This removes any such assumption using GFP_KERNEL and spin_lock_irq()
Signed-off-by: Oliver Neukum <oliver@neukum.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/usb/serial/visor.c b/drivers/usb/serial/visor.c
index 8e2d6dd..b9341f0 100644
--- a/drivers/usb/serial/visor.c
+++ b/drivers/usb/serial/visor.c
@@ -583,12 +583,11 @@
{
struct usb_serial_port *port = tty->driver_data;
struct visor_private *priv = usb_get_serial_port_data(port);
- unsigned long flags;
dbg("%s - port %d", __func__, port->number);
- spin_lock_irqsave(&priv->lock, flags);
+ spin_lock_irq(&priv->lock);
priv->throttled = 1;
- spin_unlock_irqrestore(&priv->lock, flags);
+ spin_unlock_irq(&priv->lock);
}
@@ -596,17 +595,16 @@
{
struct usb_serial_port *port = tty->driver_data;
struct visor_private *priv = usb_get_serial_port_data(port);
- unsigned long flags;
int result;
dbg("%s - port %d", __func__, port->number);
- spin_lock_irqsave(&priv->lock, flags);
+ spin_lock_irq(&priv->lock);
priv->throttled = 0;
priv->actually_throttled = 0;
- spin_unlock_irqrestore(&priv->lock, flags);
+ spin_unlock_irq(&priv->lock);
port->read_urb->dev = port->serial->dev;
- result = usb_submit_urb(port->read_urb, GFP_ATOMIC);
+ result = usb_submit_urb(port->read_urb, GFP_KERNEL);
if (result)
dev_err(&port->dev,
"%s - failed submitting read urb, error %d\n",