Skip to content

Commit

Permalink
m68k/psc: Fix race in installing chained IRQ handler
Browse files Browse the repository at this point in the history
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: Joshua Thompson <funaho@jurai.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: linux-m68k@lists.linux-m68k.org
  • Loading branch information
Thomas Gleixner committed Jun 25, 2015
1 parent bf54da7 commit 09c5cb9
Showing 1 changed file with 4 additions and 8 deletions.
12 changes: 4 additions & 8 deletions arch/m68k/mac/psc.c
Original file line number Diff line number Diff line change
Expand Up @@ -148,14 +148,10 @@ static void psc_irq(unsigned int irq, struct irq_desc *desc)

void __init psc_register_interrupts(void)
{
irq_set_chained_handler(IRQ_AUTO_3, psc_irq);
irq_set_handler_data(IRQ_AUTO_3, (void *)0x30);
irq_set_chained_handler(IRQ_AUTO_4, psc_irq);
irq_set_handler_data(IRQ_AUTO_4, (void *)0x40);
irq_set_chained_handler(IRQ_AUTO_5, psc_irq);
irq_set_handler_data(IRQ_AUTO_5, (void *)0x50);
irq_set_chained_handler(IRQ_AUTO_6, psc_irq);
irq_set_handler_data(IRQ_AUTO_6, (void *)0x60);
irq_set_chained_handler_and_data(IRQ_AUTO_3, psc_irq, (void *)0x30);
irq_set_chained_handler_and_data(IRQ_AUTO_4, psc_irq, (void *)0x40);
irq_set_chained_handler_and_data(IRQ_AUTO_5, psc_irq, (void *)0x50);
irq_set_chained_handler_and_data(IRQ_AUTO_6, psc_irq, (void *)0x60);
}

void psc_irq_enable(int irq) {
Expand Down

0 comments on commit 09c5cb9

Please sign in to comment.