Commit 8497d6a2 authored Apr 12, 2011 by Sebastian Ott Committed by Greg Kroah-Hartman Apr 22, 2011

driver-core: fix race between device_register and driver_register



When a device is registered to a bus it will be a) added to the list
of devices of the bus and b) bind to a driver (if one matches). As a
result of a driver being registered at this bus between a) and b) this
device could already be bound to a driver. This leads to a warning
and incorrect refcounting.
To fix this add a check to device_attach to identify an already bound
device.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

parent fc271199

drivers/base/dd.c

+5 −0

Original line number	Diff line number	Diff line
		@@ -245,6 +245,10 @@ int device_attach(struct device *dev)

		device_lock(dev);
		if (dev->driver) {
		if (klist_node_attached(&dev->p->knode_driver)) {
		ret = 1;
		goto out_unlock;
		}
		ret = device_bind_driver(dev);
		if (ret == 0)
		ret = 1;
		@@ -257,6 +261,7 @@ int device_attach(struct device *dev)
		ret = bus_for_each_drv(dev->bus, NULL, dev, __device_attach);
		pm_runtime_put_sync(dev);
		}
		out_unlock:
		device_unlock(dev);
		return ret;
		}