Re: [PATCH -tip] irq: DEBUG_SHIRQ executed on irq setup failure

From: Thomas Gleixner
Date: Wed Apr 01 2009 - 06:17:27 EST


On Tue, 31 Mar 2009, Luis Henriques wrote:

> When requesting an IRQ, the DEBUG_SHIRQ code executes a fake IRQ just to make
> sure the driver is ready to receive an IRQ immediately. The problem was that
> this fake IRQ was being executed even if interrupt line failed to be allocated
> by __setup_irq.

Good point !

> Signed-off-by: Luis Henriques <henrix@xxxxxxx>
> ---
> kernel/irq/manage.c | 2 +-
> 1 files changed, 1 insertions(+), 1 deletions(-)
>
> diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
> index a3eb7ba..8e1be16 100644
> --- a/kernel/irq/manage.c
> +++ b/kernel/irq/manage.c
> @@ -914,7 +914,7 @@ int request_threaded_irq(unsigned int irq, irq_handler_t handler,
> kfree(action);
>
> #ifdef CONFIG_DEBUG_SHIRQ
> - if (irqflags & IRQF_SHARED) {
> + if (retval && (irqflags & IRQF_SHARED)) {

!retval might actually prevent the situation you described above :)

Thanks,

tglx
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