Re: [patch] mfd: 88pm80x: Double shifting bug in suspend/resume

From: Lee Jones
Date: Tue Aug 09 2016 - 09:49:19 EST


On Thu, 04 Aug 2016, Dan Carpenter wrote:

> set_bit() and clear_bit() take the bit number so this code is really
> doing "1 << (1 << irq)" which is a double shift bug. It's done
> consistently so it won't cause a problem unless "irq" is more than 4.
>
> Fixes: 70c6cce04066 ('mfd: Support 88pm80x in 80x driver')
> Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>

Applied, thanks.

> diff --git a/include/linux/mfd/88pm80x.h b/include/linux/mfd/88pm80x.h
> index d409ceb..c118a7e 100644
> --- a/include/linux/mfd/88pm80x.h
> +++ b/include/linux/mfd/88pm80x.h
> @@ -350,7 +350,7 @@ static inline int pm80x_dev_suspend(struct device *dev)
> int irq = platform_get_irq(pdev, 0);
>
> if (device_may_wakeup(dev))
> - set_bit((1 << irq), &chip->wu_flag);
> + set_bit(irq, &chip->wu_flag);
>
> return 0;
> }
> @@ -362,7 +362,7 @@ static inline int pm80x_dev_resume(struct device *dev)
> int irq = platform_get_irq(pdev, 0);
>
> if (device_may_wakeup(dev))
> - clear_bit((1 << irq), &chip->wu_flag);
> + clear_bit(irq, &chip->wu_flag);
>
> return 0;
> }

--
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org â Open source software for ARM SoCs
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