Merge branch 'writeback-for-2.6.34' into nfs-for-2.6.34

1 files changed, 1 insertions, 1 deletions

diff --git a/kernel/pid.c b/kernel/pid.c
index 2e17c9c92cbe..b08e697cd83f 100644
--- a/kernel/pid.c
+++ b/kernel/pid.c
@@ -367,7 +367,7 @@ struct task_struct *pid_task(struct pid *pid, enum pid_type type)
         struct task_struct *result = NULL;
         if (pid) {
                 struct hlist_node *first;
-                first = rcu_dereference(pid->tasks[type].first);
+                first = rcu_dereference_check(pid->tasks[type].first, rcu_read_lock_held() || lockdep_is_held(&tasklist_lock));
                 if (first)
                         result = hlist_entry(first, struct task_struct, pids[(type)].node);
         }