genirq: Warn if enable_irq is called before irq is set up
The recent changes in the genirq core unearthed a bug in arch/um which
called enable_irq() before the interrupt was set up.
Warn and return instead of crashing the machine with a NULL pointer
dereference.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Richard Weinberger <richard@nod.at>
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index 644e8d5..5f92acc5 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -324,6 +324,10 @@
if (!desc)
return;
+ if (WARN(!desc->irq_data.chip || !desc->irq_data.chip->irq_enable,
+ KERN_ERR "enable_irq before setup/request_irq: irq %u\n", irq))
+ return;
+
chip_bus_lock(desc);
raw_spin_lock_irqsave(&desc->lock, flags);
__enable_irq(desc, irq, false);