USB: usb-serial: replace shutdown with disconnect, release
This patch (as1254) splits up the shutdown method of usb_serial_driver
into a disconnect and a release method.
The problem is that the usb-serial core was calling shutdown during
disconnect handling, but drivers didn't expect it to be called until
after all the open file references had been closed. The result was an
oops when the close method tried to use memory that had been
deallocated by shutdown.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/usb/serial/usb-serial.c b/drivers/usb/serial/usb-serial.c
index da890f0..d595aa5 100644
--- a/drivers/usb/serial/usb-serial.c
+++ b/drivers/usb/serial/usb-serial.c
@@ -141,6 +141,14 @@
if (serial->minor != SERIAL_TTY_NO_MINOR)
return_serial(serial);
+ serial->type->release(serial);
+
+ for (i = 0; i < serial->num_ports; ++i) {
+ port = serial->port[i];
+ if (port)
+ put_device(&port->dev);
+ }
+
/* If this is a "fake" port, we have to clean it up here, as it will
* not get cleaned up in port_release() as it was never registered with
* the driver core */
@@ -148,9 +156,8 @@
for (i = serial->num_ports;
i < serial->num_port_pointers; ++i) {
port = serial->port[i];
- if (!port)
- continue;
- port_free(port);
+ if (port)
+ port_free(port);
}
}
@@ -1118,10 +1125,6 @@
serial->disconnected = 1;
mutex_unlock(&serial->disc_mutex);
- /* Unfortunately, many of the sub-drivers expect the port structures
- * to exist when their shutdown method is called, so we have to go
- * through this awkward two-step unregistration procedure.
- */
for (i = 0; i < serial->num_ports; ++i) {
port = serial->port[i];
if (port) {
@@ -1153,14 +1156,7 @@
}
}
}
- serial->type->shutdown(serial);
- for (i = 0; i < serial->num_ports; ++i) {
- port = serial->port[i];
- if (port) {
- put_device(&port->dev);
- serial->port[i] = NULL;
- }
- }
+ serial->type->disconnect(serial);
/* let the last holder of this object
* cause it to be cleaned up */
@@ -1338,7 +1334,8 @@
set_to_generic_if_null(device, chars_in_buffer);
set_to_generic_if_null(device, read_bulk_callback);
set_to_generic_if_null(device, write_bulk_callback);
- set_to_generic_if_null(device, shutdown);
+ set_to_generic_if_null(device, disconnect);
+ set_to_generic_if_null(device, release);
}
int usb_serial_register(struct usb_serial_driver *driver)