Re: [PATCH] gpio: dwapb: Add robust error handling in interrupt handler

[Linus Walleij]

Hi Liang,

thanks for your patch!

Top posting so tglx get the context...

On Fri, Jul 3, 2026 at 3:49 PM Liang Hao <haohlliang@xxxxxxxxx> wrote:

> The current interrupt handler silently continues if an interrupt
> handling fails, which may lead to interrupt storms. Add proper
> error handling to gracefully recover from failed interrupt
> handling.
>
> When generic_handle_irq() fails, the following recovery actions are
> taken:
>   - Write EOI to clear the pending interrupt
>   - Mask the interrupt to prevent immediate re-triggering
>   - Disable the interrupt to stop further interrupts on this line
>
> These measures prevent the system from being overwhelmed by repeated
> unhandled interrupts while logging a rate-limited warning for
> debugging purposes.
>
> Signed-off-by: Liang Hao <haohlliang@xxxxxxxxx>
> ---
>  drivers/gpio/gpio-dwapb.c | 16 ++++++++++++++--
>  1 file changed, 14 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpio/gpio-dwapb.c b/drivers/gpio/gpio-dwapb.c
> index 7b92b233fafe..dec700e3cfb0 100644
> --- a/drivers/gpio/gpio-dwapb.c
> +++ b/drivers/gpio/gpio-dwapb.c
> @@ -209,8 +209,20 @@ static u32 dwapb_do_irq(struct dwapb_gpio *gpio)
>         for_each_set_bit(hwirq, &irq_status, DWAPB_MAX_GPIOS) {
>                 int gpio_irq = irq_find_mapping(gen_gc->gc.irq.domain, hwirq);
>                 u32 irq_type = irq_get_trigger_type(gpio_irq);
> -
> -               generic_handle_irq(gpio_irq);
> +               int ret;
> +               u32 val_intmask, val_inten;
> +
> +               ret = generic_handle_irq(gpio_irq);
> +               if (ret) {
> +                       dev_warn_ratelimited(gpio->dev, "Failed to handle irq %d\n", gpio_irq);
> +                       /* Clear the interrupt */
> +                       dwapb_write(gpio, GPIO_PORTA_EOI, BIT(hwirq));
> +                       val_intmask = dwapb_read(gpio, GPIO_INTMASK);
> +                       dwapb_write(gpio, GPIO_INTMASK, val_intmask | BIT(hwirq));
> +                       val_inten = dwapb_read(gpio, GPIO_INTEN);
> +                       dwapb_write(gpio, GPIO_INTEN, val_inten & ~BIT(hwirq));
> +                       continue;
> +               }
>
>                 if ((irq_type & IRQ_TYPE_SENSE_MASK) == IRQ_TYPE_EDGE_BOTH)
>                         dwapb_toggle_trigger(gpio, hwirq);

Ugh I don't know if that is how you'r supposed to deal with the return value
from generic_handle_irq(), we better get tglx eyes on this.

Yours,
Linus Walleij