kobject: grab the kset reference in kobject_add, not kobject_init

kobject_init should not be grabing any references, but only initializing
the object.  This patch fixes this, and makes the lock hold-time shorter
for when a kset is present in the kobject.

The current kernel tree has been audited to verify that this change
should be safe.

Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/lib/kobject.c b/lib/kobject.c
index 7919c32..4d52b6f 100644 (file)
--- a/lib/kobject.c
+++ b/lib/kobject.c
@@ -133,7 +133,6 @@ void kobject_init(struct kobject * kobj)
                return;
        kref_init(&kobj->kref);
        INIT_LIST_HEAD(&kobj->entry);
-       kobj->kset = kset_get(kobj->kset);
 }
 
 
@@ -184,7 +183,7 @@ int kobject_add(struct kobject * kobj)
                 kobj->kset ? kobject_name(&kobj->kset->kobj) : "<NULL>" );
 
        if (kobj->kset) {
-               spin_lock(&kobj->kset->list_lock);
+               kobj->kset = kset_get(kobj->kset);
 
                if (!parent) {
                        parent = kobject_get(&kobj->kset->kobj);
@@ -196,7 +195,8 @@ int kobject_add(struct kobject * kobj)
                        kobject_get(parent);
                }
 
-               list_add_tail(&kobj->entry,&kobj->kset->list);
+               spin_lock(&kobj->kset->list_lock);
+               list_add_tail(&kobj->entry, &kobj->kset->list);
                spin_unlock(&kobj->kset->list_lock);
                kobj->parent = parent;
        }