sparseirq: make for_each_irq_desc() more robust
Raja reported for_each_irq_desc() has possibility unsafeness:
if anyone write folliwing code, for_each_irq_desc() doesn't work
as intended:
(right now this code does not exist at all)
if (safe)
for_each_irq_desc(irq, desc) {
...
}
else
panic();
Reported-by: Raja R Harinath <harinath@hurrynot.org>
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/include/linux/irqnr.h b/include/linux/irqnr.h
index 86af92e..52ebbb4 100644
--- a/include/linux/irqnr.h
+++ b/include/linux/irqnr.h
@@ -28,13 +28,17 @@
# define for_each_irq_desc(irq, desc) \
for (irq = 0, desc = irq_to_desc(irq); irq < nr_irqs; \
irq++, desc = irq_to_desc(irq)) \
- if (desc)
+ if (!desc) \
+ ; \
+ else
# define for_each_irq_desc_reverse(irq, desc) \
for (irq = nr_irqs - 1, desc = irq_to_desc(irq); irq >= 0; \
irq--, desc = irq_to_desc(irq)) \
- if (desc)
+ if (!desc) \
+ ; \
+ else
#endif /* CONFIG_GENERIC_HARDIRQS */