[PATCH] USB console: fix disconnection issues
Prevent sending further output to a USB-serial console after the dongle is
disconnected, take care not to leak kref.
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/usb/serial/console.c b/drivers/usb/serial/console.c
index fc4a0f7..f3404e1 100644
--- a/drivers/usb/serial/console.c
+++ b/drivers/usb/serial/console.c
@@ -202,7 +202,7 @@
struct usb_serial *serial;
int retval = -ENODEV;
- if (!port)
+ if (!port || port->serial->dev->state == USB_STATE_NOTATTACHED)
return;
serial = port->serial;
@@ -255,6 +255,14 @@
.index = -1,
};
+void usb_serial_console_disconnect(struct usb_serial *serial)
+{
+ if (serial && serial->port && serial->port[0] && serial->port[0] == usbcons_info.port) {
+ usb_serial_console_exit();
+ usb_serial_put(serial);
+ }
+}
+
void usb_serial_console_init (int serial_debug, int minor)
{
debug = serial_debug;
@@ -280,6 +288,11 @@
void usb_serial_console_exit (void)
{
- unregister_console(&usbcons);
+ if (usbcons_info.port) {
+ unregister_console(&usbcons);
+ if (usbcons_info.port->open_count)
+ usbcons_info.port->open_count--;
+ usbcons_info.port = NULL;
+ }
}
diff --git a/drivers/usb/serial/usb-serial.c b/drivers/usb/serial/usb-serial.c
index de9111d..92200f0 100644
--- a/drivers/usb/serial/usb-serial.c
+++ b/drivers/usb/serial/usb-serial.c
@@ -168,6 +168,11 @@
kfree (serial);
}
+void usb_serial_put(struct usb_serial *serial)
+{
+ kref_put(&serial->kref, destroy_serial);
+}
+
/*****************************************************************************
* Driver tty interface functions
*****************************************************************************/
@@ -232,7 +237,7 @@
port->open_count = 0;
mutex_unlock(&port->mutex);
bailout_kref_put:
- kref_put(&serial->kref, destroy_serial);
+ usb_serial_put(serial);
return retval;
}
@@ -268,7 +273,7 @@
}
mutex_unlock(&port->mutex);
- kref_put(&port->serial->kref, destroy_serial);
+ usb_serial_put(port->serial);
}
static int serial_write (struct tty_struct * tty, const unsigned char *buf, int count)
@@ -276,7 +281,7 @@
struct usb_serial_port *port = tty->driver_data;
int retval = -EINVAL;
- if (!port)
+ if (!port || port->serial->dev->state == USB_STATE_NOTATTACHED)
goto exit;
dbg("%s - port %d, %d byte(s)", __FUNCTION__, port->number, count);
@@ -473,7 +478,7 @@
begin += length;
length = 0;
}
- kref_put(&serial->kref, destroy_serial);
+ usb_serial_put(serial);
}
*eof = 1;
done:
@@ -985,6 +990,7 @@
struct device *dev = &interface->dev;
struct usb_serial_port *port;
+ usb_serial_console_disconnect(serial);
dbg ("%s", __FUNCTION__);
usb_set_intfdata (interface, NULL);
@@ -996,7 +1002,7 @@
}
/* let the last holder of this object
* cause it to be cleaned up */
- kref_put(&serial->kref, destroy_serial);
+ usb_serial_put(serial);
}
dev_info(dev, "device disconnected\n");
}
diff --git a/drivers/usb/serial/usb-serial.h b/drivers/usb/serial/usb-serial.h
index dc89d87..c07ece3 100644
--- a/drivers/usb/serial/usb-serial.h
+++ b/drivers/usb/serial/usb-serial.h
@@ -248,13 +248,16 @@
#ifdef CONFIG_USB_SERIAL_CONSOLE
extern void usb_serial_console_init (int debug, int minor);
extern void usb_serial_console_exit (void);
+extern void usb_serial_console_disconnect(struct usb_serial *serial);
#else
static inline void usb_serial_console_init (int debug, int minor) { }
static inline void usb_serial_console_exit (void) { }
+static inline void usb_serial_console_disconnect(struct usb_serial *serial) {}
#endif
/* Functions needed by other parts of the usbserial core */
extern struct usb_serial *usb_serial_get_by_index (unsigned int minor);
+extern void usb_serial_put(struct usb_serial *serial);
extern int usb_serial_generic_open (struct usb_serial_port *port, struct file *filp);
extern int usb_serial_generic_write (struct usb_serial_port *port, const unsigned char *buf, int count);
extern void usb_serial_generic_close (struct usb_serial_port *port, struct file *filp);