3 files changed, 11 insertions, 11 deletions

diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c
index 5fe03def34b2..2cc682b860ea 100644
--- a/block/blk-cgroup.c
+++ b/block/blk-cgroup.c
@@ -286,16 +286,16 @@ done:
 static struct cgroup_subsys_state *
 blkiocg_create(struct cgroup_subsys *subsys, struct cgroup *cgroup)
 {
-        struct blkio_cgroup *blkcg, *parent_blkcg;
+        struct blkio_cgroup *blkcg;
+        struct cgroup *parent = cgroup->parent;
 
-        if (!cgroup->parent) {
+        if (!parent) {
                 blkcg = &blkio_root_cgroup;
                 goto done;
         }
 
         /* Currently we do not support hierarchy deeper than two level (0,1) */
-        parent_blkcg = cgroup_to_blkio_cgroup(cgroup->parent);
-        if (css_depth(&parent_blkcg->css) > 0)
+        if (parent != cgroup->top_cgroup)
                 return ERR_PTR(-EINVAL);
 
         blkcg = kzalloc(sizeof(*blkcg), GFP_KERNEL);
diff --git a/block/blk-timeout.c b/block/blk-timeout.c
index 1ba7e0aca878..4f0c06c7a338 100644
--- a/block/blk-timeout.c
+++ b/block/blk-timeout.c
@@ -109,6 +109,7 @@ void blk_rq_timed_out_timer(unsigned long data)
         struct request_queue *q = (struct request_queue *) data;
         unsigned long flags, next = 0;
         struct request *rq, *tmp;
+        int next_set = 0;
 
         spin_lock_irqsave(q->queue_lock, flags);
 
@@ -122,16 +123,13 @@ void blk_rq_timed_out_timer(unsigned long data)
                         if (blk_mark_rq_complete(rq))
                                 continue;
                         blk_rq_timed_out(rq);
-                } else if (!next || time_after(next, rq->deadline))
+                } else if (!next_set || time_after(next, rq->deadline)) {
                         next = rq->deadline;
+                        next_set = 1;
+                }
         }
 
-        /*
-         * next can never be 0 here with the list non-empty, since we always
-         * bump ->deadline to 1 so we can detect if the timer was ever added
-         * or not. See comment in blk_add_timer()
-         */
-        if (next)
+        if (next_set)
                 mod_timer(&q->timeout, round_jiffies_up(next));
 
         spin_unlock_irqrestore(q->queue_lock, flags);
diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c
index 838834be115b..5f127cfb2e92 100644
--- a/block/cfq-iosched.c
+++ b/block/cfq-iosched.c
@@ -3694,8 +3694,10 @@ static void *cfq_init_queue(struct request_queue *q)
          * to make sure that cfq_put_cfqg() does not try to kfree root group
          */
         atomic_set(&cfqg->ref, 1);
+        rcu_read_lock();
         blkiocg_add_blkio_group(&blkio_root_cgroup, &cfqg->blkg, (void *)cfqd,
                                         0);
+        rcu_read_unlock();
 #endif
         /*
          * Not strictly needed (since RB_ROOT just clears the node and we