Messages in this thread Patch in this message | | | Date | Fri, 22 Feb 2008 16:31:20 -0800 | From | Greg KH <> | Subject | [patch 30/38] genirq: do not leave interupts enabled on free_irq |
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2.6.24-stable review patch. If anyone has any objections, please let us know.
------------------ From: Thomas Gleixner <tglx@linutronix.de>
commit 89d694b9dbe769ca1004e01db0ca43964806a611
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.
Pointed-out-by: Michael Hennerich <Michael.Hennerich@analog.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Ingo Molnar <mingo@elte.hu> Tested-by: Michael Hennerich <Michael.Hennerich@analog.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
--- kernel/irq/chip.c | 20 +++++++++++++++++++- 1 file changed, 19 insertions(+), 1 deletion(-)
--- a/kernel/irq/chip.c +++ b/kernel/irq/chip.c @@ -246,6 +246,17 @@ static unsigned int default_startup(unsi } /* + * 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 */ void irq_chip_set_defaults(struct irq_chip *chip) @@ -256,8 +267,15 @@ void irq_chip_set_defaults(struct irq_ch 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) --
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