driver-core: do not register a driver with bus_type not registered

If the bus_type is not registerd, driver_register to that bus will cause oops.

I found this bug when test built-in usb serial drivers (ie. aircable driver)
with 'nousb' cmdline params.

In this patch:
1. set the bus->p=NULL when bus_register failed and unregisterd.
2. if bus->p is NULL, driver_register BUG_ON will be triggered.

Signed-off-by: Dave Young <hidave.darkstar@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Dave Young 2009-02-14 21:23:22 +08:00 committed by Greg Kroah-Hartman
parent e5779a583d
commit f48f3febb2
2 changed files with 4 additions and 0 deletions

View file

@ -932,6 +932,7 @@ int bus_register(struct bus_type *bus)
kset_unregister(&bus->p->subsys);
kfree(bus->p);
out:
bus->p = NULL;
return retval;
}
EXPORT_SYMBOL_GPL(bus_register);
@ -953,6 +954,7 @@ void bus_unregister(struct bus_type *bus)
bus_remove_file(bus, &bus_attr_uevent);
kset_unregister(&bus->p->subsys);
kfree(bus->p);
bus->p = NULL;
}
EXPORT_SYMBOL_GPL(bus_unregister);

View file

@ -216,6 +216,8 @@ int driver_register(struct device_driver *drv)
int ret;
struct device_driver *other;
BUG_ON(!drv->bus->p);
if ((drv->bus->probe && drv->probe) ||
(drv->bus->remove && drv->remove) ||
(drv->bus->shutdown && drv->shutdown))