4 files changed, 47 insertions, 5 deletions

diff --git a/arch/x86/kernel/irq_64.c b/arch/x86/kernel/irq_64.c
index a3e36336d914..f58b995b30ee 100644
--- a/arch/x86/kernel/irq_64.c
+++ b/arch/x86/kernel/irq_64.c
@@ -189,6 +189,7 @@ u64 arch_irq_stat(void)
 asmlinkage unsigned int do_IRQ(struct pt_regs *regs)
 {
         struct pt_regs *old_regs = set_irq_regs(regs);
+        struct irq_desc *desc;
 
         /* high bit used in ret_from_ code  */
         unsigned vector = ~regs->orig_ax;
@@ -202,8 +203,9 @@ asmlinkage unsigned int do_IRQ(struct pt_regs *regs)
         stack_overflow_check(regs);
 #endif
 
-        if (likely(__irq_to_desc(irq)))
-                generic_handle_irq(irq);
+        desc = __irq_to_desc(irq);
+        if (likely(desc))
+                generic_handle_irq_desc(irq, desc);
         else {
                 if (!disable_apic)
                         ack_APIC_irq();
diff --git a/include/linux/irq.h b/include/linux/irq.h
index 9de16ca8b8e5..7b59e193a119 100644
--- a/include/linux/irq.h
+++ b/include/linux/irq.h
@@ -315,10 +315,8 @@ extern unsigned int __do_IRQ(unsigned int irq);
  * irqchip-style controller then we call the ->handle_irq() handler,
  * and it calls __do_IRQ() if it's attached to an irqtype-style controller.
  */
-static inline void generic_handle_irq(unsigned int irq)
+static inline void generic_handle_irq_desc(unsigned int irq, struct irq_desc *desc)
 {
-        struct irq_desc *desc = irq_to_desc(irq);
-
 #ifdef CONFIG_GENERIC_HARDIRQS_NO__DO_IRQ
         desc->handle_irq(irq, desc);
 #else
@@ -329,6 +327,11 @@ static inline void generic_handle_irq(unsigned int irq)
 #endif
 }
 
+static inline void generic_handle_irq(unsigned int irq)
+{
+        generic_handle_irq_desc(irq, irq_to_desc(irq));
+}
+
 /* Handling of unhandled and spurious interrupts: */
 extern void note_interrupt(unsigned int irq, struct irq_desc *desc,
                            int action_ret);
diff --git a/init/main.c b/init/main.c
index ab97d0877acc..0d2e60144f83 100644
--- a/init/main.c
+++ b/init/main.c
@@ -590,6 +590,13 @@ void pre_alloc_dyn_array(void)
                 if (da->init_work)
                         da->init_work(da);
         }
+#else
+#ifdef CONFIF_GENERIC_HARDIRQS
+        unsigned int i;
+
+        for (i = 0; i < NR_IRQS; i++)
+                irq_desc[i].irq = i;
+#endif
 #endif
 }
 
diff --git a/kernel/irq/handle.c b/kernel/irq/handle.c
index 8e55dbe50afc..e1d787e9169b 100644
--- a/kernel/irq/handle.c
+++ b/kernel/irq/handle.c
@@ -197,6 +197,21 @@ struct irq_desc *irq_to_desc(unsigned int irq)
          *  we run out of pre-allocate ones, allocate more
          */
         printk(KERN_DEBUG "try to get more irq_desc %d\n", nr_irq_desc);
+        {
+                /* double check if some one mess up the list */
+                struct irq_desc *desc;
+                int count = 0;
+
+                desc = &sparse_irqs[0];
+                while (desc) {
+                        printk(KERN_DEBUG "found irq_desc for irq %d\n", desc->irq);
+                        if (desc->next)
+                                printk(KERN_DEBUG "found irq_desc for irq %d and next will be irq %d\n", desc->irq, desc->next->irq);
+                        desc = desc->next;
+                        count++;
+                }
+                printk(KERN_DEBUG "all preallocted %d\n", count);
+        }
 
         total_bytes = sizeof(struct irq_desc) * nr_irq_desc;
         if (after_bootmem)
@@ -221,6 +236,21 @@ struct irq_desc *irq_to_desc(unsigned int irq)
 
         desc->irq = irq;
         desc_pri->next = desc;
+        {
+                /* double check if some one mess up the list */
+                struct irq_desc *desc;
+                int count = 0;
+
+                desc = &sparse_irqs[0];
+                while (desc) {
+                        printk(KERN_DEBUG "1 found irq_desc for irq %d\n", desc->irq);
+                        if (desc->next)
+                                printk(KERN_DEBUG "1 found irq_desc for irq %d and next will be irq %d\n", desc->irq, desc->next->irq);
+                        desc = desc->next;
+                        count++;
+                }
+                printk(KERN_DEBUG "1 all preallocted %d\n", count);
+        }
 
         return desc;
 }