From 89d694b9dbe769ca1004e01db0ca43964806a611 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Mon, 18 Feb 2008 18:25:17 +0100 Subject: genirq: do not leave interupts enabled on free_irq The default_disable() function was changed in commit: 76d2160147f43f982dfe881404cfde9fd0a9da21 genirq: do not mask interrupts by default It removed the mask function in favour of the default delayed interrupt disabling. Unfortunately this also broke the shutdown in free_irq() when the last handler is removed from the interrupt for those architectures which rely on the default implementations. Now we can end up with a enabled interrupt line after the last handler was removed, which can result in spurious interrupts. Fix this by adding a default_shutdown function, which is only installed, when the irqchip implementation does provide neither a shutdown nor a disable function. [@stable: affected versions: .21 - .24 ] Pointed-out-by: Michael Hennerich Signed-off-by: Thomas Gleixner Acked-by: Ingo Molnar Cc: stable@kernel.org Tested-by: Michael Hennerich --- kernel/irq/chip.c | 20 +++++++++++++++++++- 1 file changed, 19 insertions(+), 1 deletion(-) (limited to 'kernel') diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c index cc54c627635..fdb3fbe2b0c 100644 --- a/kernel/irq/chip.c +++ b/kernel/irq/chip.c @@ -245,6 +245,17 @@ static unsigned int default_startup(unsigned int irq) return 0; } +/* + * default shutdown function + */ +static void default_shutdown(unsigned int irq) +{ + struct irq_desc *desc = irq_desc + irq; + + desc->chip->mask(irq); + desc->status |= IRQ_MASKED; +} + /* * Fixup enable/disable function pointers */ @@ -256,8 +267,15 @@ void irq_chip_set_defaults(struct irq_chip *chip) chip->disable = default_disable; if (!chip->startup) chip->startup = default_startup; + /* + * We use chip->disable, when the user provided its own. When + * we have default_disable set for chip->disable, then we need + * to use default_shutdown, otherwise the irq line is not + * disabled on free_irq(): + */ if (!chip->shutdown) - chip->shutdown = chip->disable; + chip->shutdown = chip->disable != default_disable ? + chip->disable : default_shutdown; if (!chip->name) chip->name = chip->typename; if (!chip->end) -- cgit v1.2.3