2 files changed, 15 insertions, 5 deletions

diff --git a/kernel/lockdep.c b/kernel/lockdep.c
index 0f389621bb6b..723bd9f92556 100644
--- a/kernel/lockdep.c
+++ b/kernel/lockdep.c
@@ -2654,10 +2654,15 @@ static void check_flags(unsigned long flags)
         if (!debug_locks)
                 return;
 
-        if (irqs_disabled_flags(flags))
-                DEBUG_LOCKS_WARN_ON(current->hardirqs_enabled);
-        else
-                DEBUG_LOCKS_WARN_ON(!current->hardirqs_enabled);
+        if (irqs_disabled_flags(flags)) {
+                if (DEBUG_LOCKS_WARN_ON(current->hardirqs_enabled)) {
+                        printk("possible reason: unannotated irqs-off.\n");
+                }
+        } else {
+                if (DEBUG_LOCKS_WARN_ON(!current->hardirqs_enabled)) {
+                        printk("possible reason: unannotated irqs-on.\n");
+                }
+        }
 
         /*
          * We dont accurately track softirq state in e.g.
diff --git a/kernel/sched.c b/kernel/sched.c
index 67d9d1799d86..c6e551de795b 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -488,7 +488,12 @@ unsigned long long cpu_clock(int cpu)
 
         local_irq_save(flags);
         rq = cpu_rq(cpu);
-        update_rq_clock(rq);
+        /*
+         * Only call sched_clock() if the scheduler has already been
+         * initialized (some code might call cpu_clock() very early):
+         */
+        if (rq->idle)
+                update_rq_clock(rq);
         now = rq->clock;
         local_irq_restore(flags);