Merge branch 'linus' into sched/core

Resolve cherry-picking conflicts:

Conflicts:
	mm/huge_memory.c
	mm/memory.c
	mm/mprotect.c

See this upstream merge commit for more details:

  52469b4fcd Merge branch 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Signed-off-by: Ingo Molnar <mingo@kernel.org>

lib/Kconfig.debug

@@ -983,7 +983,7 @@ 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

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);