[PATCH] genirq:Dereference desc after null pointer check

[RAGHU Halharvi]

* Remove unchecked dereferencing of *desc & assigning it local irq
        variable
* Move the assignement after proper check of *desc for NULL pointer.

Signed-off-by: RAGHU Halharvi <raghuhac...@gmail.com>
---
 kernel/irq/manage.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index facfecfc543c..33c77eb4fdb6 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -1557,15 +1557,16 @@ EXPORT_SYMBOL_GPL(setup_irq);
  */
 static struct irqaction *__free_irq(struct irq_desc *desc, void *dev_id)
 {
-       unsigned irq = desc->irq_data.irq;
+       unsigned int irq;
        struct irqaction *action, **action_ptr;
        unsigned long flags;
 
-       WARN(in_interrupt(), "Trying to free IRQ %d from IRQ context!\n", irq);
 
        if (!desc)
                return NULL;
 
+       irq = desc->irq_data.irq;
+       WARN(in_interrupt(), "Trying to free IRQ %d from IRQ context!\n", irq);
        mutex_lock(&desc->request_mutex);
        chip_bus_lock(desc);
        raw_spin_lock_irqsave(&desc->lock, flags);
-- 
2.17.1