[PATCH] driver core: fix error handling in bus_add_device

The error handling in bus_add_device() and device_attach() is simply
non-existing. This patch propagates any error from device_attach to
the upper layers to allow for a proper recovery.

From: Hannes Reinecke <hare@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

2 files changed, 10 insertions, 6 deletions

diff --git a/drivers/base/bus.c b/drivers/base/bus.c
index 4eb19525e064..43722af90bdd 100644
--- a/drivers/base/bus.c
+++ b/drivers/base/bus.c
@@ -270,11 +270,14 @@ int bus_add_device(struct device * dev)
 
         if (bus) {
                 pr_debug("bus %s: add device %s\n", bus->name, dev->bus_id);
-                device_attach(dev);
+                error = device_attach(dev);
                 klist_add_tail(&bus->klist_devices, &dev->knode_bus);
-                device_add_attrs(bus, dev);
-                sysfs_create_link(&bus->devices.kobj, &dev->kobj, dev->bus_id);
-                sysfs_create_link(&dev->kobj, &dev->bus->subsys.kset.kobj, "bus");
+                if (error >= 0)
+                        error = device_add_attrs(bus, dev);
+                if (!error) {
+                        sysfs_create_link(&bus->devices.kobj, &dev->kobj, dev->bus_id);
+                        sysfs_create_link(&dev->kobj, &dev->bus->subsys.kset.kobj, "bus");
+                }
         }
         return error;
 }
@@ -394,7 +397,7 @@ static int bus_rescan_devices_helper(struct device *dev, void *data)
 {
         int *count = data;
 
-        if (!dev->driver && device_attach(dev))
+        if (!dev->driver && (device_attach(dev) > 0))
                 (*count)++;
 
         return 0;
diff --git a/drivers/base/dd.c b/drivers/base/dd.c
index eab2030c506d..6db3a789c54f 100644
--- a/drivers/base/dd.c
+++ b/drivers/base/dd.c
@@ -119,7 +119,8 @@ static int __device_attach(struct device_driver * drv, void * data)
  *      driver_probe_device() for each pair. If a compatible
  *      pair is found, break out and return.
  *
- *      Returns 1 if the device was bound to a driver; 0 otherwise.
+ *      Returns 1 if the device was bound to a driver;
+ *      0 if no matching device was found; error code otherwise.
  */
 int device_attach(struct device * dev)
 {