From a34a9d57f287071e2d0d7223d4c23d11850d3aef Mon Sep 17 00:00:00 2001
From: Tejun Heo <tj@kernel.org>
Date: Thu, 20 Dec 2012 15:05:40 -0800
Subject: [PATCH] --- yaml --- r: 347884 b: refs/heads/master c:
 154b454edaf6d94a69016db6c342c57fa935bbe9 h: refs/heads/master v: v3

---
 [refs]                |  2 +-
 trunk/mm/memcontrol.c | 14 +++++++++++++-
 2 files changed, 14 insertions(+), 2 deletions(-)

diff --git a/[refs] b/[refs]
index 957115e8b89e..066df1d25017 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 495e9d84607cda966ba6d223d5eb9df0070cd21a
+refs/heads/master: 154b454edaf6d94a69016db6c342c57fa935bbe9
diff --git a/trunk/mm/memcontrol.c b/trunk/mm/memcontrol.c
index f3009b4bae51..09255ec8159c 100644
--- a/trunk/mm/memcontrol.c
+++ b/trunk/mm/memcontrol.c
@@ -6090,7 +6090,6 @@ mem_cgroup_css_alloc(struct cgroup *cont)
 						&per_cpu(memcg_stock, cpu);
 			INIT_WORK(&stock->work, drain_local_stock);
 		}
-		hotcpu_notifier(memcg_cpu_hotplug_callback, 0);
 	} else {
 		parent = mem_cgroup_from_cont(cont->parent);
 		memcg->use_hierarchy = parent->use_hierarchy;
@@ -6756,6 +6755,19 @@ struct cgroup_subsys mem_cgroup_subsys = {
 	.use_id = 1,
 };
 
+/*
+ * The rest of init is performed during ->css_alloc() for root css which
+ * happens before initcalls.  hotcpu_notifier() can't be done together as
+ * it would introduce circular locking by adding cgroup_lock -> cpu hotplug
+ * dependency.  Do it from a subsys_initcall().
+ */
+static int __init mem_cgroup_init(void)
+{
+	hotcpu_notifier(memcg_cpu_hotplug_callback, 0);
+	return 0;
+}
+subsys_initcall(mem_cgroup_init);
+
 #ifdef CONFIG_MEMCG_SWAP
 static int __init enable_swap_account(char *s)
 {