Commit 73e487fd authored by Guennadi Liakhovetski's avatar Guennadi Liakhovetski Committed by Greg Kroah-Hartman

[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: default avatarGuennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent ca85485c
......@@ -202,7 +202,7 @@ static void usb_console_write(struct console *co, const char *buf, unsigned coun
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 @@ static struct console usbcons = {
.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_init (int serial_debug, int minor)
void usb_serial_console_exit (void)
{
if (usbcons_info.port) {
unregister_console(&usbcons);
if (usbcons_info.port->open_count)
usbcons_info.port->open_count--;
usbcons_info.port = NULL;
}
}
......@@ -168,6 +168,11 @@ static void destroy_serial(struct kref *kref)
kfree (serial);
}
void usb_serial_put(struct usb_serial *serial)
{
kref_put(&serial->kref, destroy_serial);
}
/*****************************************************************************
* Driver tty interface functions
*****************************************************************************/
......@@ -232,7 +237,7 @@ static int serial_open (struct tty_struct *tty, struct file * filp)
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 @@ static void serial_close(struct tty_struct *tty, struct file * filp)
}
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 @@ static int serial_write (struct tty_struct * tty, const unsigned char *buf, int
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 @@ static int serial_read_proc (char *page, char **start, off_t off, int count, int
begin += length;
length = 0;
}
kref_put(&serial->kref, destroy_serial);
usb_serial_put(serial);
}
*eof = 1;
done:
......@@ -985,6 +990,7 @@ void usb_serial_disconnect(struct usb_interface *interface)
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 @@ void usb_serial_disconnect(struct usb_interface *interface)
}
/* 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");
}
......
......@@ -248,13 +248,16 @@ extern int ezusb_set_reset (struct usb_serial *serial, unsigned char reset_bit);
#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);
......
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