From: Thomas Gleixner <tglx@linutronix.de>
Date: Sun, 21 Jun 2015 19:00:38 +0000 (+0200)
Subject: MIPS/pci: Fix race in installing chained IRQ handler
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=746ad9a7a1fef789a9f579441b4a7b686fa85aa2;p=GitHub%2FLineageOS%2FG12%2Fandroid_kernel_amlogic_linux-4.9.git

MIPS/pci: 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: Wolfram Sang <wsa@the-dreams.de>
Cc: Sergey Ryazanov <ryazanov.s.a@gmail.com>
Cc: linux-mips@linux-mips.org
---

diff --git a/arch/mips/pci/pci-ar2315.c b/arch/mips/pci/pci-ar2315.c
index 07a18228e63a..9627c9345139 100644
--- a/arch/mips/pci/pci-ar2315.c
+++ b/arch/mips/pci/pci-ar2315.c
@@ -384,8 +384,8 @@ static void ar2315_pci_irq_init(struct ar2315_pci_ctrl *apc)
 
 	apc->irq_ext = irq_create_mapping(apc->domain, AR2315_PCI_IRQ_EXT);
 
-	irq_set_chained_handler(apc->irq, ar2315_pci_irq_handler);
-	irq_set_handler_data(apc->irq, apc);
+	irq_set_chained_handler_and_data(apc->irq, ar2315_pci_irq_handler,
+					 apc);
 
 	/* Clear any pending Abort or external Interrupts
 	 * and enable interrupt processing */