Re: [PATCH v2] gpio: max732x: Fix irq-events handler

[Linus Walleij <linus.walleij@xxxxxxxxxx>]

On Wed, Apr 22, 2015 at 3:20 PM, Semen Protsenko
<semen.protsenko@xxxxxxxxxxxxxxx> wrote:

> MAX732X clears all pending interrupts on I2C read (when interrupts
> register is being read). Driver doesn't need to send any ACKs when
> interrupt was handled. So replace handle_edge_irq() with
> handle_simple_irq().
>
> Using handle_edge_irq() (w/o .irq_ack callback set) may lead to NULL
> pointer dereference in some cases. E.g. this was observed on
> hibernation process:
>
>   Unable to handle kernel NULL pointer dereference at virtual address 0
>   Backtrace:
>   (handle_edge_irq) from (resend_irqs)
>   (resend_irqs) from (tasklet_action)
>   (tasklet_action) from (__do_softirq)
>   (__do_softirq) from (run_ksoftirqd)
>   (run_ksoftirqd) from (smpboot_thread_fn)
>   (smpboot_thread_fn) from (kthread)
>   (kthread) from (ret_from_fork)
>
> Signed-off-by: Semen Protsenko <semen.protsenko@xxxxxxxxxxxxxxx>

Patch applied with Grygorii's Review tag.

Yours,
Linus Walleij
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