4 files changed, 96 insertions, 7 deletions

diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 29329374ff0d..ebef88f61b7d 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -992,7 +992,7 @@ config DEBUG_KOBJECT
 
 config DEBUG_KOBJECT_RELEASE
         bool "kobject release debugging"
-        depends on DEBUG_KERNEL
+        depends on DEBUG_OBJECTS_TIMERS
         help
           kobjects are reference counted objects.  This means that their
           last reference count put is not predictable, and the kobject can
diff --git a/lib/kobject.c b/lib/kobject.c
index 669bf190d4fb..7a1c203083eb 100644
--- a/lib/kobject.c
+++ b/lib/kobject.c
@@ -13,11 +13,33 @@
  */
 
 #include <linux/kobject.h>
+#include <linux/kobj_completion.h>
 #include <linux/string.h>
 #include <linux/export.h>
 #include <linux/stat.h>
 #include <linux/slab.h>
 
+/**
+ * kobject_namespace - return @kobj's namespace tag
+ * @kobj: kobject in question
+ *
+ * Returns namespace tag of @kobj if its parent has namespace ops enabled
+ * and thus @kobj should have a namespace tag associated with it.  Returns
+ * %NULL otherwise.
+ */
+const void *kobject_namespace(struct kobject *kobj)
+{
+        const struct kobj_ns_type_operations *ns_ops = kobj_ns_ops(kobj);
+        const void *ns;
+
+        if (!ns_ops || ns_ops->type == KOBJ_NS_TYPE_NONE)
+                return NULL;
+
+        ns = kobj->ktype->namespace(kobj);
+        WARN_ON(!ns);   /* @kobj in a namespace is required to have !NULL tag */
+        return ns;
+}
+
 /*
  * populate_dir - populate directory with attributes.
  * @kobj: object we're working on.
@@ -46,13 +68,21 @@ static int populate_dir(struct kobject *kobj)
 
 static int create_dir(struct kobject *kobj)
 {
-        int error = 0;
-        error = sysfs_create_dir(kobj);
+        int error;
+
+        error = sysfs_create_dir_ns(kobj, kobject_namespace(kobj));
         if (!error) {
                 error = populate_dir(kobj);
                 if (error)
                         sysfs_remove_dir(kobj);
         }
+
+        /*
+         * @kobj->sd may be deleted by an ancestor going away.  Hold an
+         * extra reference so that it stays until @kobj is gone.
+         */
+        sysfs_get(kobj->sd);
+
         return error;
 }
 
@@ -428,7 +458,7 @@ int kobject_rename(struct kobject *kobj, const char *new_name)
                 goto out;
         }
 
-        error = sysfs_rename_dir(kobj, new_name);
+        error = sysfs_rename_dir_ns(kobj, new_name, kobject_namespace(kobj));
         if (error)
                 goto out;
 
@@ -472,6 +502,7 @@ int kobject_move(struct kobject *kobj, struct kobject *new_parent)
                 if (kobj->kset)
                         new_parent = kobject_get(&kobj->kset->kobj);
         }
+
         /* old object path */
         devpath = kobject_get_path(kobj, GFP_KERNEL);
         if (!devpath) {
@@ -486,7 +517,7 @@ int kobject_move(struct kobject *kobj, struct kobject *new_parent)
         sprintf(devpath_string, "DEVPATH_OLD=%s", devpath);
         envp[0] = devpath_string;
         envp[1] = NULL;
-        error = sysfs_move_dir(kobj, new_parent);
+        error = sysfs_move_dir_ns(kobj, new_parent, kobject_namespace(kobj));
         if (error)
                 goto out;
         old_parent = kobj->parent;
@@ -508,10 +539,15 @@ out:
  */
 void kobject_del(struct kobject *kobj)
 {
+        struct sysfs_dirent *sd;
+
         if (!kobj)
                 return;
 
+        sd = kobj->sd;
         sysfs_remove_dir(kobj);
+        sysfs_put(sd);
+
         kobj->state_in_sysfs = 0;
         kobj_kset_leave(kobj);
         kobject_put(kobj->parent);
@@ -592,7 +628,7 @@ static void kobject_release(struct kref *kref)
 {
         struct kobject *kobj = container_of(kref, struct kobject, kref);
 #ifdef CONFIG_DEBUG_KOBJECT_RELEASE
-        pr_debug("kobject: '%s' (%p): %s, parent %p (delayed)\n",
+        pr_info("kobject: '%s' (%p): %s, parent %p (delayed)\n",
                  kobject_name(kobj), kobj, __func__, kobj->parent);
         INIT_DELAYED_WORK(&kobj->release, kobject_delayed_cleanup);
         schedule_delayed_work(&kobj->release, HZ);
@@ -727,6 +763,55 @@ const struct sysfs_ops kobj_sysfs_ops = {
 };
 
 /**
+ * kobj_completion_init - initialize a kobj_completion object.
+ * @kc: kobj_completion
+ * @ktype: type of kobject to initialize
+ *
+ * kobj_completion structures can be embedded within structures with different
+ * lifetime rules.  During the release of the enclosing object, we can
+ * wait on the release of the kobject so that we don't free it while it's
+ * still busy.
+ */
+void kobj_completion_init(struct kobj_completion *kc, struct kobj_type *ktype)
+{
+        init_completion(&kc->kc_unregister);
+        kobject_init(&kc->kc_kobj, ktype);
+}
+EXPORT_SYMBOL_GPL(kobj_completion_init);
+
+/**
+ * kobj_completion_release - release a kobj_completion object
+ * @kobj: kobject embedded in kobj_completion
+ *
+ * Used with kobject_release to notify waiters that the kobject has been
+ * released.
+ */
+void kobj_completion_release(struct kobject *kobj)
+{
+        struct kobj_completion *kc = kobj_to_kobj_completion(kobj);
+        complete(&kc->kc_unregister);
+}
+EXPORT_SYMBOL_GPL(kobj_completion_release);
+
+/**
+ * kobj_completion_del_and_wait - release the kobject and wait for it
+ * @kc: kobj_completion object to release
+ *
+ * Delete the kobject from sysfs and drop the reference count.  Then wait
+ * until any other outstanding references are also dropped.  This routine
+ * is only necessary once other references may have been taken on the
+ * kobject.  Typically this happens when the kobject has been published
+ * to sysfs via kobject_add.
+ */
+void kobj_completion_del_and_wait(struct kobj_completion *kc)
+{
+        kobject_del(&kc->kc_kobj);
+        kobject_put(&kc->kc_kobj);
+        wait_for_completion(&kc->kc_unregister);
+}
+EXPORT_SYMBOL_GPL(kobj_completion_del_and_wait);
+
+/**
  * kset_register - initialize and add a kset.
  * @k: kset.
  */
diff --git a/lib/percpu-refcount.c b/lib/percpu-refcount.c
index 7deeb6297a48..1a53d497a8c5 100644
--- a/lib/percpu-refcount.c
+++ b/lib/percpu-refcount.c
@@ -53,6 +53,7 @@ int percpu_ref_init(struct percpu_ref *ref, percpu_ref_func_t *release)
         ref->release = release;
         return 0;
 }
+EXPORT_SYMBOL_GPL(percpu_ref_init);
 
 /**
  * percpu_ref_cancel_init - cancel percpu_ref_init()
@@ -84,6 +85,7 @@ void percpu_ref_cancel_init(struct percpu_ref *ref)
                 free_percpu(ref->pcpu_count);
         }
 }
+EXPORT_SYMBOL_GPL(percpu_ref_cancel_init);
 
 static void percpu_ref_kill_rcu(struct rcu_head *rcu)
 {
@@ -156,3 +158,4 @@ void percpu_ref_kill_and_confirm(struct percpu_ref *ref,
 
         call_rcu_sched(&ref->rcu, percpu_ref_kill_rcu);
 }
+EXPORT_SYMBOL_GPL(percpu_ref_kill_and_confirm);
diff --git a/lib/scatterlist.c b/lib/scatterlist.c
index a685c8a79578..d16fa295ae1d 100644
--- a/lib/scatterlist.c
+++ b/lib/scatterlist.c
@@ -577,7 +577,8 @@ void sg_miter_stop(struct sg_mapping_iter *miter)
                 miter->__offset += miter->consumed;
                 miter->__remaining -= miter->consumed;
 
-                if (miter->__flags & SG_MITER_TO_SG)
+                if ((miter->__flags & SG_MITER_TO_SG) &&
+                    !PageSlab(miter->page))
                         flush_kernel_dcache_page(miter->page);
 
                 if (miter->__flags & SG_MITER_ATOMIC) {