[PATCH 3.14 14/38] clockevents: sun5i: Fix setup_irq init sequence

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

3.14-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Yongbae Park <yongbae2@gmail.com>

commit 1096be084ac59927158ce80ff1d31c33eed0e565 upstream.

The interrupt is enabled before the handler is set. Even this bug
did not appear, it is potentially dangerous as it can lead to a
NULL pointer dereference.

Fix the error by enabling the interrupt after
clockevents_config_and_register() is called.

Signed-off-by: Yongbae Park <yongbae2@gmail.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/clocksource/timer-sun5i.c |    8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

--- a/drivers/clocksource/timer-sun5i.c
+++ b/drivers/clocksource/timer-sun5i.c
@@ -172,10 +172,6 @@ static void __init sun5i_timer_init(stru
 
 	ticks_per_jiffy = DIV_ROUND_UP(rate, HZ);
 
-	ret = setup_irq(irq, &sun5i_timer_irq);
-	if (ret)
-		pr_warn("failed to setup irq %d\n", irq);
-
 	/* Enable timer0 interrupt */
 	val = readl(timer_base + TIMER_IRQ_EN_REG);
 	writel(val | TIMER_IRQ_EN(0), timer_base + TIMER_IRQ_EN_REG);
@@ -185,6 +181,10 @@ static void __init sun5i_timer_init(stru
 
 	clockevents_config_and_register(&sun5i_clockevent, rate,
 					TIMER_SYNC_TICKS, 0xffffffff);
+
+	ret = setup_irq(irq, &sun5i_timer_irq);
+	if (ret)
+		pr_warn("failed to setup irq %d\n", irq);
 }
 CLOCKSOURCE_OF_DECLARE(sun5i_a13, "allwinner,sun5i-a13-hstimer",
 		       sun5i_timer_init);