Re: [tip:irq/core] genirq: Warn if enable_irq is called before irq isset up

From: Richard Weinberger
Date: Fri Oct 22 2010 - 09:43:28 EST


On Fri, 22 Oct 2010 13:09:49 GMT, tip-bot for Thomas Gleixner
<tglx@xxxxxxxxxxxxx> wrote:
> Commit-ID: 658fc358f9954083ea55abf82ca77a18f82412d7
> Gitweb:
> http://git.kernel.org/tip/658fc358f9954083ea55abf82ca77a18f82412d7
> Author: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
> AuthorDate: Fri, 22 Oct 2010 14:47:57 +0200
> Committer: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
> CommitDate: Fri, 22 Oct 2010 15:05:35 +0200
>
> genirq: Warn if enable_irq is called before irq is set up
>
> The recent changes in the genirq core unearthed a bug in arch/um which
> called enable_irq() before the interrupt was set up.
>
> Warn and return instead of crashing the machine with a NULL pointer
> dereference.
>
> Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
> Cc: Richard Weinberger <richard@xxxxxx>
> ---
> kernel/irq/manage.c | 4 ++++
> 1 files changed, 4 insertions(+), 0 deletions(-)
>
> diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
> index 644e8d5..2806023 100644
> --- a/kernel/irq/manage.c
> +++ b/kernel/irq/manage.c
> @@ -324,6 +324,10 @@ void enable_irq(unsigned int irq)
> if (!desc)
> return;
>
> + if (WARN(!desc->irq_data.chip || !desc->irq_data.chip->irq_enable,
> + "KERN_ERR enable_irq before setup/request_irq: irq %u\n", irq))

Here is a little typo. The double quote should be after KERN_ERR.

Thanks,
//richard

> + return;
> +
> chip_bus_lock(desc);
> raw_spin_lock_irqsave(&desc->lock, flags);
> __enable_irq(desc, irq, false);

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