Re: [PATCH] mfd: hi655x-pmic: fix IRQ action memory leak on removal

[Guangshuo Li]

Hi Lee,

Thank you for your suggestion.

On Wed, 28 Oct 2026 at 00:25, Lee Jones <lee@xxxxxxxxxx> wrote:
>
> On Tue, 27 Oct 2026, Guangshuo Li wrote:
>
> > hi655x_pmic_remove() currently removes the regmap IRQ chip before
> > removing the MFD child devices. regmap_del_irq_chip() disposes the
> > child IRQ mappings and removes their IRQ descriptors.
> >
> > The hi65xx-powerkey child registers interrupt handlers using
> > devm_request_any_context_irq(). During child device removal, the
> > device-managed cleanup calls free_irq(), but the corresponding IRQ
> > descriptors are no longer available. As a result, the allocated
> > struct irqaction objects referenced by irq_desc->action are not
> > freed, causing a memory leak.
> >
> > Remove the MFD child devices first, allowing their device-managed
> > IRQ handlers to be released while the IRQ mappings are still valid.
> > Then remove the regmap IRQ chip and its IRQ domain.
> >
> > This issue was found by our static analysis tool under development.
> >
> > Fixes: eb10245fb37e ("mfd: hi655x-pmic: Add powerkey device to hi655x PMIC driver")
> > Cc: stable@xxxxxxxxxxxxxxx
> > Signed-off-by: Guangshuo Li <lgs201920130244@xxxxxxxxx>
> > ---
> >  drivers/mfd/hi655x-pmic.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/drivers/mfd/hi655x-pmic.c b/drivers/mfd/hi655x-pmic.c
> > index 5cb392892c19..3a7ccc9d30b7 100644
> > --- a/drivers/mfd/hi655x-pmic.c
> > +++ b/drivers/mfd/hi655x-pmic.c
> > @@ -147,8 +147,8 @@ static void hi655x_pmic_remove(struct platform_device *pdev)
> >  {
> >       struct hi655x_pmic *pmic = platform_get_drvdata(pdev);
> >
> > -     regmap_del_irq_chip(gpiod_to_irq(pmic->gpio), pmic->irq_data);
> >       mfd_remove_devices(&pdev->dev);
> > +     regmap_del_irq_chip(gpiod_to_irq(pmic->gpio), pmic->irq_data);
>
> What about devm_regmap_add_irq_chip() and devm_mfd_*()?
>
> >  }
> >
> >  static const struct of_device_id hi655x_pmic_match[] = {
> > --
> > 2.43.0
> >
>
> --
> Lee Jones

I agree that using devm_regmap_add_irq_chip() and
devm_mfd_add_devices() would be a cleaner and more appropriate
approach, as it would allow the resource cleanup order to be managed
automatically.

I'll look into this approach and update the patch accordingly.

Thanks again for your guidance.

Best regards,
Guangshuo Li