xen/events: Add WARN_ON when quick lookup found invalid type.

All of the bind_XYZ_to_irq do a quick lookup to see if the
event exists. And if it does, then the initialized IRQ number
is returned instead of initializing a new IRQ number.

This patch adds an extra logic to check that the type returned
is proper one and that there is an IRQ handler setup for it.

This patch has the benefit of being able to find drivers that
are doing something naught.

[v1: Enhanced based on Stefano's review]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>

diff --git a/drivers/xen/events.c b/drivers/xen/events.c
index 6908e4ce2a0d69aa67ca0e11251d834770bbd68c..7595581d032cc9d9c5a7f04ee12b861dc76051ee 100644 (file)
--- a/drivers/xen/events.c
+++ b/drivers/xen/events.c
@@ -827,6 +827,9 @@ int bind_evtchn_to_irq(unsigned int evtchn)
                                              handle_edge_irq, "event");
 
                xen_irq_info_evtchn_init(irq, evtchn);
+       } else {
+               struct irq_info *info = info_for_irq(irq);
+               WARN_ON(info == NULL || info->type != IRQT_EVTCHN);
        }
 
 out:
@@ -862,6 +865,9 @@ static int bind_ipi_to_irq(unsigned int ipi, unsigned int cpu)
                xen_irq_info_ipi_init(cpu, irq, evtchn, ipi);
 
                bind_evtchn_to_cpu(evtchn, cpu);
+       } else {
+               struct irq_info *info = info_for_irq(irq);
+               WARN_ON(info == NULL || info->type != IRQT_IPI);
        }
 
  out:
@@ -939,6 +945,9 @@ int bind_virq_to_irq(unsigned int virq, unsigned int cpu)
                xen_irq_info_virq_init(cpu, irq, evtchn, virq);
 
                bind_evtchn_to_cpu(evtchn, cpu);
+       } else {
+               struct irq_info *info = info_for_irq(irq);
+               WARN_ON(info == NULL || info->type != IRQT_VIRQ);
        }
 
 out: