4 files changed, 26 insertions, 10 deletions

diff --git a/kernel/fork.c b/kernel/fork.c
index 3da978eec791..8cdd3e72ba55 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -1315,9 +1315,8 @@ struct task_struct * __devinit fork_idle(int cpu)
         struct pt_regs regs;
 
         task = copy_process(CLONE_VM, 0, idle_regs(&regs), 0, NULL, NULL, 0);
-        if (!task)
-                return ERR_PTR(-ENOMEM);
-        init_idle(task, cpu);
+        if (!IS_ERR(task))
+                init_idle(task, cpu);
 
         return task;
 }
diff --git a/kernel/irq/handle.c b/kernel/irq/handle.c
index 42aa6f1a3f0f..a681912bc89a 100644
--- a/kernel/irq/handle.c
+++ b/kernel/irq/handle.c
@@ -231,10 +231,10 @@ fastcall unsigned int __do_IRQ(unsigned int irq)
                 spin_unlock(&desc->lock);
 
                 action_ret = handle_IRQ_event(irq, action);
-
-                spin_lock(&desc->lock);
                 if (!noirqdebug)
                         note_interrupt(irq, desc, action_ret);
+
+                spin_lock(&desc->lock);
                 if (likely(!(desc->status & IRQ_PENDING)))
                         break;
                 desc->status &= ~IRQ_PENDING;
diff --git a/kernel/irq/spurious.c b/kernel/irq/spurious.c
index 9c7e2e4c1fe7..543ea2e5ad93 100644
--- a/kernel/irq/spurious.c
+++ b/kernel/irq/spurious.c
@@ -147,11 +147,7 @@ void note_interrupt(unsigned int irq, struct irq_desc *desc,
         if (unlikely(irqfixup)) {
                 /* Don't punish working computers */
                 if ((irqfixup == 2 && irq == 0) || action_ret == IRQ_NONE) {
-                        int ok;
-
-                        spin_unlock(&desc->lock);
-                        ok = misrouted_irq(irq);
-                        spin_lock(&desc->lock);
+                        int ok = misrouted_irq(irq);
                         if (action_ret == IRQ_NONE)
                                 desc->irqs_unhandled -= ok;
                 }
diff --git a/kernel/spinlock.c b/kernel/spinlock.c
index 476c3741511b..2c6c2bf85514 100644
--- a/kernel/spinlock.c
+++ b/kernel/spinlock.c
@@ -293,6 +293,27 @@ void __lockfunc _spin_lock_nested(spinlock_t *lock, int subclass)
 }
 
 EXPORT_SYMBOL(_spin_lock_nested);
+unsigned long __lockfunc _spin_lock_irqsave_nested(spinlock_t *lock, int subclass)
+{
+        unsigned long flags;
+
+        local_irq_save(flags);
+        preempt_disable();
+        spin_acquire(&lock->dep_map, subclass, 0, _RET_IP_);
+        /*
+         * On lockdep we dont want the hand-coded irq-enable of
+         * _raw_spin_lock_flags() code, because lockdep assumes
+         * that interrupts are not re-enabled during lock-acquire:
+         */
+#ifdef CONFIG_PROVE_SPIN_LOCKING
+        _raw_spin_lock(lock);
+#else
+        _raw_spin_lock_flags(lock, &flags);
+#endif
+        return flags;
+}
+
+EXPORT_SYMBOL(_spin_lock_irqsave_nested);
 
 #endif