powerpc: Make virq_debug_show() cope with sparse irq_descs

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

diff --git a/arch/powerpc/kernel/irq.c b/arch/powerpc/kernel/irq.c
index 65632215f020a16723b27b7b3ae69d956d037618..baa49eb93228e0774274c976e28f30e57bda8058 100644 (file)
--- a/arch/powerpc/kernel/irq.c
+++ b/arch/powerpc/kernel/irq.c
@@ -1065,8 +1065,11 @@ static int virq_debug_show(struct seq_file *m, void *private)
        seq_printf(m, "%-5s  %-7s  %-15s  %s\n", "virq", "hwirq",
                      "chip name", "host name");
 
-       for (i = 1; i < NR_IRQS; i++) {
+       for (i = 1; i < nr_irqs; i++) {
                desc = irq_to_desc(i);
+               if (!desc)
+                       continue;
+
                spin_lock_irqsave(&desc->lock, flags);
 
                if (desc->action && desc->action->handler) {