commit 5c1642e4d2e475bbfb13da15c6ca16a23ba889bb
author Thomas Gleixner <tglx@linutronix.de> Sun Jun 21 21:00:43 2015 +0200
committer Thomas Gleixner <tglx@linutronix.de> Thu Jun 25 11:58:01 2015 +0200
tree f0d146b47857c6da121efc1a123c9b15a1ecfffd
parent 746ad9a7a1fef789a9f579441b4a7b686fa85aa2

MIPS/ralink: 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: Ralf Baechle <ralf@linux-mips.org>
Cc: Qais Yousef <qais.yousef@imgtec.com>
Cc: Andrew Bresticker <abrestic@chromium.org>
Cc: John Crispin <blogic@openwrt.org>
Cc: linux-mips@linux-mips.org

arch/mips/ralink/irq.c

diff --git a/arch/mips/ralink/irq.c b/arch/mips/ralink/irq.c
index 7cf91b9..f044299 100644
--- a/arch/mips/ralink/irq.c
+++ b/arch/mips/ralink/irq.c
@@ -184,8 +184,7 @@
 
 	rt_intc_w32(INTC_INT_GLOBAL, INTC_REG_ENABLE);
 
-	irq_set_chained_handler(irq, ralink_intc_irq_handler);
-	irq_set_handler_data(irq, domain);
+	irq_set_chained_handler_and_data(irq, ralink_intc_irq_handler, domain);
 
 	/* tell the kernel which irq is used for performance monitoring */
 	rt_perfcount_irq = irq_create_mapping(domain, 9);