[PATCH v2 2/3] drivers/base/class: __class_register(): make error behaviour consistent

From: Nicolai Stange
Date: Wed Nov 18 2015 - 11:48:39 EST


If a class attribute's sysfs creation fails at the very end of
__class_register(), the kset object already registered for the class itself
is not unregistered again.

This is not consistent with the other possible failures of
__class_register() for which nothing is left over to be manually released
by the caller.

Since class attribute creation does not fail in the real world, the
impact is minimal -- this patch is a cosmetic one.

Make __class_register() follow all-or-nothing semantics, i.e. unregister
the already registered cp->subsys kset object on attribute creation
failure.

Signed-off-by: Nicolai Stange <nicstange@xxxxxxxxx>
---
drivers/base/class.c | 6 ++++++
1 file changed, 6 insertions(+)

diff --git a/drivers/base/class.c b/drivers/base/class.c
index c9683cf..fc663d0 100644
--- a/drivers/base/class.c
+++ b/drivers/base/class.c
@@ -225,6 +225,12 @@ int __class_register(struct class *cls, struct lock_class_key *key)
}
error = add_class_attrs(class_get(cls));
class_put(cls);
+ if (error) {
+ /* as above, clear cp->class on error */
+ cp->class = NULL;
+ cls->p = NULL;
+ kset_put(&cp->subsys);
+ }
return error;
}
EXPORT_SYMBOL_GPL(__class_register);
--
2.6.3

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/