On 29-08-2014 09:19 AM, Bjorn Andersson wrote: > On Thu 28 Aug 00:13 PDT 2014, Pramod Gurav wrote: > >> On Thursday 28 August 2014 02:54 AM, Bjorn Andersson wrote: >>> On Wed, Aug 27, 2014 at 3:57 AM, Pramod Gurav >>> <pramod.gurav@xxxxxxxxxxxxxxx> wrote: >>>> This patches adds a call to gpiochip_remove_pin_ranges when >>>> gpiochip_irqchip_add fails to release memory allocated for pin_ranges. >>>> >>>> diff --git a/drivers/pinctrl/qcom/pinctrl-msm.c b/drivers/pinctrl/qcom/pinctrl-msm.c >>>> @@ -845,6 +845,7 @@ static int msm_gpio_init(struct msm_pinctrl *pctrl) >>>> IRQ_TYPE_NONE); >>>> if (ret) { >>>> dev_err(pctrl->dev, "Failed to add irqchip to gpiochip\n"); >>>> + gpiochip_remove_pin_ranges(chip); >>>> return -ENOSYS; >>>> } >>> >>> Good catch, I guess this was lost in the introduction of gpiochip_irqchip... >>> >>> >>> Rather than just releasing the pin_ranges of the gpio_chip you should >>> probably add a gpiochip_remove() both here and in the case of >>> gpiochip_add_pin_range() failing. >> >> Thanks for review. But if I see implementation of gpiochip_remove() it does: >> gpiochip_irqchip_remove(chip); >> gpiochip_remove_pin_ranges(chip); >> of_gpiochip_remove(chip); >> >> In above failure case only gpiochip_add() and gpiochip_add_pin_range() >> have been successful hence I thought that would cause any problem to add >> gpiochip_remove(). If that is not a problem I think we can call >> gpiochip_remove() in fail case of gpiochip_add_pin_range() as well. >> Do I make sense? >> > > As soon as gpiochip_add() have returned successfully we will have a live > gpio_chip, upon returning unsuccessfully from probe devres will free the pctrl > node and the gpio core will continue to operate on freed memory. > > Therefor we need to call gpio_remove() in the ccase of both > gpiochip_add_pin_range() and gpiochip_irqchip_add() failing. > > The gpio_remove() does as you say remove those additional items, but handles > the case where they are not yet "allocated". > > I hope this answers your conserns. That really does. Thanks for your time. Will resend the patch with handling failure cases of both gpiochip_add_pin_range() and gpiochip_irqchip_add(). > > Regards, > Bjorn > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ > -- To unsubscribe from this list: send the line "unsubscribe linux-arm-msm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html