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@xxxxxxxxx> --- drivers/base/bus.c | 2 ++ drivers/base/driver.c | 2 ++ 2 files changed, 4 insertions(+) diff -uprN a/drivers/base/bus.c b/drivers/base/bus.c --- a/drivers/base/bus.c 2009-02-14 20:47:24.441149465 +0800 +++ b/drivers/base/bus.c 2009-02-14 20:49:42.350149362 +0800 @@ -932,6 +932,7 @@ bus_uevent_fail: 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); diff -uprN a/drivers/base/driver.c b/drivers/base/driver.c --- a/drivers/base/driver.c 2009-02-14 20:47:38.048149854 +0800 +++ b/drivers/base/driver.c 2009-02-14 20:47:50.692141034 +0800 @@ -216,6 +216,8 @@ int driver_register(struct device_driver 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)) -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
