3 files changed, 30 insertions, 12 deletions

diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 3f21cc79a134..2869307ca3e4 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -8,6 +8,13 @@ config PRINTK_TIME
           operations.  This is useful for identifying long delays
           in kernel startup.
 
+config ENABLE_MUST_CHECK
+        bool "Enable __must_check logic"
+        default y
+        help
+          Enable the __must_check logic in the kernel build.  Disable this to
+          suppress the "warning: ignoring return value of 'foo', declared with
+          attribute warn_unused_result" messages.
 
 config MAGIC_SYSRQ
         bool "Magic SysRq key"
diff --git a/lib/klist.c b/lib/klist.c
index 9c94f0b163a1..120bd175aa78 100644
--- a/lib/klist.c
+++ b/lib/klist.c
@@ -123,12 +123,10 @@ EXPORT_SYMBOL_GPL(klist_add_tail);
 static void klist_release(struct kref * kref)
 {
         struct klist_node * n = container_of(kref, struct klist_node, n_ref);
-        void (*put)(struct klist_node *) = n->n_klist->put;
+
         list_del(&n->n_node);
         complete(&n->n_removed);
         n->n_klist = NULL;
-        if (put)
-                put(n);
 }
 
 static int klist_dec_and_del(struct klist_node * n)
@@ -145,10 +143,14 @@ static int klist_dec_and_del(struct klist_node * n)
 void klist_del(struct klist_node * n)
 {
         struct klist * k = n->n_klist;
+        void (*put)(struct klist_node *) = k->put;
 
         spin_lock(&k->k_lock);
-        klist_dec_and_del(n);
+        if (!klist_dec_and_del(n))
+                put = NULL;
         spin_unlock(&k->k_lock);
+        if (put)
+                put(n);
 }
 
 EXPORT_SYMBOL_GPL(klist_del);
@@ -161,10 +163,7 @@ EXPORT_SYMBOL_GPL(klist_del);
 
 void klist_remove(struct klist_node * n)
 {
-        struct klist * k = n->n_klist;
-        spin_lock(&k->k_lock);
-        klist_dec_and_del(n);
-        spin_unlock(&k->k_lock);
+        klist_del(n);
         wait_for_completion(&n->n_removed);
 }
 
@@ -260,12 +259,15 @@ static struct klist_node * to_klist_node(struct list_head * n)
 struct klist_node * klist_next(struct klist_iter * i)
 {
         struct list_head * next;
+        struct klist_node * lnode = i->i_cur;
         struct klist_node * knode = NULL;
+        void (*put)(struct klist_node *) = i->i_klist->put;
 
         spin_lock(&i->i_klist->k_lock);
-        if (i->i_cur) {
-                next = i->i_cur->n_node.next;
-                klist_dec_and_del(i->i_cur);
+        if (lnode) {
+                next = lnode->n_node.next;
+                if (!klist_dec_and_del(lnode))
+                        put = NULL;
         } else
                 next = i->i_head->next;
 
@@ -275,6 +277,8 @@ struct klist_node * klist_next(struct klist_iter * i)
         }
         i->i_cur = knode;
         spin_unlock(&i->i_klist->k_lock);
+        if (put && lnode)
+                put(lnode);
         return knode;
 }
 
diff --git a/lib/kobject.c b/lib/kobject.c
index 8e7c71993487..1699eb9161f3 100644
--- a/lib/kobject.c
+++ b/lib/kobject.c
@@ -407,6 +407,7 @@ static struct kobj_type dir_ktype = {
 struct kobject *kobject_add_dir(struct kobject *parent, const char *name)
 {
         struct kobject *k;
+        int ret;
 
         if (!parent)
                 return NULL;
@@ -418,7 +419,13 @@ struct kobject *kobject_add_dir(struct kobject *parent, const char *name)
         k->parent = parent;
         k->ktype = &dir_ktype;
         kobject_set_name(k, name);
-        kobject_register(k);
+        ret = kobject_register(k);
+        if (ret < 0) {
+                printk(KERN_WARNING "kobject_add_dir: "
+                        "kobject_register error: %d\n", ret);
+                kobject_del(k);
+                return NULL;
+        }
 
         return k;
 }