Re: [BUG] drivers/gpio: some possible sleep-in-atomic bugs

[Andreas Larsson]

On 2017-12-12 04:59, Jia-Ju Bai wrote:
> According to drivers/gpio/gpio-grgpio.c, the kernel module may sleep
> under a spinlock.
> The function call paths are:
> grgpio_remove (acquire the spinlock)
>    gpiochip_remove
>      gpiochip_sysfs_unregister
>        device_unregister --> may sleep
>        mutex_lock --> may sleep
>
> grgpio_remove (acquire the spinlock)
>    gpiochip_remove
>      gpiochip_sysfs_unregister
>        gpiod_free
>          __gpiod_free
>            gpiod_unexport
>              device_unregister --> may sleep
>              mutex_lock --> may sleep
>
> grgpio_remove (acquire the spinlock)
>    irq_domain_remove
>      mutex_lock --> may sleep
>
> grgpio_irq_map (acquire the spinlock)
>    request_irq --> may sleep
>
> grgpio_irq_unmap (acquire the spinlock)
>    free_irq --> may sleep
>
>
> I do not find a good way to fix them, so I only report.
> These possible bugs is found by my static analysis tool (DSAC) and
> checked by my code review.
Hi!

Thank you for reporting this. I will take a look at it.

--
Best Regards,
Andreas Larsson