Re: [PATCH] gpio: tb10x: Fix an error handling path in tb10x_gpio_probe()

[Bartosz Golaszewski]

On Sun, Sep 3, 2023 at 8:13 AM Christophe JAILLET
<christophe.jaillet@xxxxxxxxxx> wrote:
>
> If an error occurs after a successful irq_domain_add_linear() call, it
> should be undone by a corresponding irq_domain_remove(), as already done
> in the remove function.
>
> Fixes: c6ce2b6bffe5 ("gpio: add TB10x GPIO driver")
> Signed-off-by: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx>
> ---
>  drivers/gpio/gpio-tb10x.c | 6 +++++-
>  1 file changed, 5 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpio/gpio-tb10x.c b/drivers/gpio/gpio-tb10x.c
> index 78f8790168ae..f96d260a4a19 100644
> --- a/drivers/gpio/gpio-tb10x.c
> +++ b/drivers/gpio/gpio-tb10x.c
> @@ -195,7 +195,7 @@ static int tb10x_gpio_probe(struct platform_device *pdev)
>                                 handle_edge_irq, IRQ_NOREQUEST, IRQ_NOPROBE,
>                                 IRQ_GC_INIT_MASK_CACHE);
>                 if (ret)
> -                       return ret;
> +                       goto err_remove_domain;
>
>                 gc = tb10x_gpio->domain->gc->gc[0];
>                 gc->reg_base                         = tb10x_gpio->base;
> @@ -209,6 +209,10 @@ static int tb10x_gpio_probe(struct platform_device *pdev)
>         }
>
>         return 0;
> +
> +err_remove_domain:
> +       irq_domain_remove(tb10x_gpio->domain);
> +       return ret;
>  }
>
>  static int tb10x_gpio_remove(struct platform_device *pdev)
> --
> 2.34.1
>

That's not enough, you also need to dispose of all remaining mappings.
Please see drivers/gpio/gpiolib.c and how it handles the gpio_irq_chip
domain.

Bartosz