From: Thomas Gleixner <tglx@linutronix.de>
Date: Sun, 21 Jun 2015 18:16:05 +0000 (+0200)
Subject: gpio/dwapb: Fix race in installing chained IRQ handler
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=6218b88d2678523cc2f6f8e3ea1182c250d9684f;p=linux-beck.git

gpio/dwapb: Fix race in installing chained IRQ handler

Fix a race where a pending interrupt could be received and the handler
called before the handler's data has been setup, by converting to
irq_set_chained_handler_and_data().

Search and conversion was done with coccinelle:

@@
expression E1, E2, E3;
@@
(
-if (irq_set_chained_handler(E1, E3) != 0)
-   BUG();
|
-irq_set_chained_handler(E1, E3);
)
-irq_set_handler_data(E1, E2);
+irq_set_chained_handler_and_data(E1, E3, E2);

@@
expression E1, E2, E3;
@@
(
-if (irq_set_chained_handler(E1, E3) != 0)
-   BUG();
...
|
-irq_set_chained_handler(E1, E3);
...
)
-irq_set_handler_data(E1, E2);
+irq_set_chained_handler_and_data(E1, E3, E2);

Reported-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Julia Lawall <Julia.Lawall@lip6.fr>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Alexandre Courbot <gnurou@gmail.com>
Cc: linux-gpio@vger.kernel.org
---

diff --git a/drivers/gpio/gpio-dwapb.c b/drivers/gpio/gpio-dwapb.c
index 58faf04fce5d..55fa9853a7f2 100644
--- a/drivers/gpio/gpio-dwapb.c
+++ b/drivers/gpio/gpio-dwapb.c
@@ -348,8 +348,8 @@ static void dwapb_configure_irqs(struct dwapb_gpio *gpio,
 	irq_gc->chip_types[1].handler = handle_edge_irq;
 
 	if (!pp->irq_shared) {
-		irq_set_chained_handler(pp->irq, dwapb_irq_handler);
-		irq_set_handler_data(pp->irq, gpio);
+		irq_set_chained_handler_and_data(pp->irq, dwapb_irq_handler,
+						 gpio);
 	} else {
 		/*
 		 * Request a shared IRQ since where MFD would have devices