Merge commit 'linux-2.6/master' (early part) into oprofile/core

This branch depends on these apic patches:

      apic, x86: Use BIOS settings for IBS and MCE threshold interrupt LVT offsets
      apic, x86: Check if EILVT APIC registers are available (AMD only)

Signed-off-by: Robert Richter <robert.richter@amd.com>

1 files changed, 2 insertions, 1 deletions

diff --git a/kernel/pid.c b/kernel/pid.c
index d55c6fb8d087..39b65b69584f 100644
--- a/kernel/pid.c
+++ b/kernel/pid.c
@@ -401,7 +401,7 @@ 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_check(pid->tasks[type].first,
+                first = rcu_dereference_check(hlist_first_rcu(&pid->tasks[type]),
                                               rcu_read_lock_held() ||
                                               lockdep_tasklist_lock_is_held());
                 if (first)
@@ -416,6 +416,7 @@ EXPORT_SYMBOL(pid_task);
  */
 struct task_struct *find_task_by_pid_ns(pid_t nr, struct pid_namespace *ns)
 {
+        rcu_lockdep_assert(rcu_read_lock_held());
         return pid_task(find_pid_ns(nr, ns), PIDTYPE_PID);
 }