[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 <[e-mail]>
Signed-off-by: Tony Luck <[e-mail]>

arch/ia64/kernel/irq_ia64.c

···
 };
 
 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] = {
···
 	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;
···
 
 	/* 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))
···
 		} 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:
···
 			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();
···
 			 * 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);
 
 			/*