[IA64] Fix unexpected interrupt vector handling

Fix handling for spurious interrupts not being mapped to any IRQs.

Currently, spurious interrupts that are not mapped to any IRQs are
handled as IRQ 15 (== IA64_SPURIOUS_VECTOR). But it is not proper
because vector != irq. We need special handlings for such spurious
interrupts not being mapped to any IRQs.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>

arch/ia64/kernel/irq_ia64.c

@@ -82,7 +82,7 @@ struct irq_cfg irq_cfg[NR_IRQS] __read_mostly = {
 };
 
 DEFINE_PER_CPU(int[IA64_NUM_VECTORS], vector_irq) = {
-	[0 ... IA64_NUM_VECTORS - 1] = IA64_SPURIOUS_INT_VECTOR
+	[0 ... IA64_NUM_VECTORS - 1] = -1
 };
 
 static cpumask_t vector_table[IA64_NUM_VECTORS] = {
@@ -179,7 +179,7 @@ static void __clear_irq_vector(int irq)
 	domain = cfg->domain;
 	cpus_and(mask, cfg->domain, cpu_online_map);
 	for_each_cpu_mask(cpu, mask)
-		per_cpu(vector_irq, cpu)[vector] = IA64_SPURIOUS_INT_VECTOR;
+		per_cpu(vector_irq, cpu)[vector] = -1;
 	cfg->vector = IRQ_VECTOR_UNASSIGNED;
 	cfg->domain = CPU_MASK_NONE;
 	irq_status[irq] = IRQ_UNUSED;
@@ -249,7 +249,7 @@ void __setup_vector_irq(int cpu)
 
 	/* Clear vector_irq */
 	for (vector = 0; vector < IA64_NUM_VECTORS; ++vector)
-		per_cpu(vector_irq, cpu)[vector] = IA64_SPURIOUS_INT_VECTOR;
+		per_cpu(vector_irq, cpu)[vector] = -1;
 	/* Mark the inuse vectors */
 	for (irq = 0; irq < NR_IRQS; ++irq) {
 		if (!cpu_isset(cpu, irq_cfg[irq].domain))
@@ -432,10 +432,18 @@ ia64_handle_irq (ia64_vector vector, struct pt_regs *regs)
 		} else if (unlikely(IS_RESCHEDULE(vector)))
 			kstat_this_cpu.irqs[vector]++;
 		else {
+			int irq = local_vector_to_irq(vector);
+
 			ia64_setreg(_IA64_REG_CR_TPR, vector);
 			ia64_srlz_d();
 
-			generic_handle_irq(local_vector_to_irq(vector));
+			if (unlikely(irq < 0)) {
+				printk(KERN_ERR "%s: Unexpected interrupt "
+				       "vector %d on CPU %d is not mapped "
+				       "to any IRQ!\n", __FUNCTION__, vector,
+				       smp_processor_id());
+			} else
+				generic_handle_irq(irq);
 
 			/*
 			 * Disable interrupts and send EOI:
@@ -483,6 +491,7 @@ void ia64_process_pending_intr(void)
 			kstat_this_cpu.irqs[vector]++;
 		else {
 			struct pt_regs *old_regs = set_irq_regs(NULL);
+			int irq = local_vector_to_irq(vector);
 
 			ia64_setreg(_IA64_REG_CR_TPR, vector);
 			ia64_srlz_d();
@@ -493,8 +502,15 @@ void ia64_process_pending_intr(void)
 			 * it will work. I hope it works!.
 			 * Probably could shared code.
 			 */
-			vectors_in_migration[local_vector_to_irq(vector)]=0;
-			generic_handle_irq(local_vector_to_irq(vector));
+			if (unlikely(irq < 0)) {
+				printk(KERN_ERR "%s: Unexpected interrupt "
+				       "vector %d on CPU %d not being mapped "
+				       "to any IRQ!!\n", __FUNCTION__, vector,
+				       smp_processor_id());
+			} else {
+				vectors_in_migration[irq]=0;
+				generic_handle_irq(irq);
+			}
 			set_irq_regs(old_regs);
 
 			/*