diff mbox

pinctrl: qcom: Release pin ranges when gpiochip_irqchip_add fails

Message ID 1409137049-15848-1-git-send-email-pramod.gurav@smartplayin.com (mailing list archive)
State Superseded, archived
Headers show

Commit Message

Pramod Gurav Aug. 27, 2014, 10:57 a.m. UTC
This patches adds a call to gpiochip_remove_pin_ranges when
gpiochip_irqchip_add fails to release memory allocated for pin_ranges.

CC: Ivan T. Ivanov <iivanov@mm-sol.com>
CC: Bjorn Andersson <bjorn.andersson@sonymobile.com>
CC: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Pramod Gurav <pramod.gurav@smartplayin.com>
---
 drivers/pinctrl/qcom/pinctrl-msm.c |    1 +
 1 file changed, 1 insertion(+)

Comments

Bjorn Andersson Aug. 27, 2014, 9:24 p.m. UTC | #1
On Wed, Aug 27, 2014 at 3:57 AM, Pramod Gurav
<pramod.gurav@smartplayin.com> 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.

Regards,
Bjorn
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Pramod Gurav Aug. 28, 2014, 7:13 a.m. UTC | #2
On Thursday 28 August 2014 02:54 AM, Bjorn Andersson wrote:
> On Wed, Aug 27, 2014 at 3:57 AM, Pramod Gurav
> <pramod.gurav@smartplayin.com> 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?

> 
> Regards,
> Bjorn
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Bjorn Andersson Aug. 29, 2014, 3:49 a.m. UTC | #3
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@smartplayin.com> 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.

Regards,
Bjorn
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Pramod Gurav Aug. 29, 2014, 7:19 a.m. UTC | #4
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@smartplayin.com> 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
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Linus Walleij Sept. 2, 2014, 12:29 p.m. UTC | #5
On Wed, Aug 27, 2014 at 12:57 PM, Pramod Gurav
<pramod.gurav@smartplayin.com> wrote:

> This patches adds a call to gpiochip_remove_pin_ranges when
> gpiochip_irqchip_add fails to release memory allocated for pin_ranges.
>
> CC: Ivan T. Ivanov <iivanov@mm-sol.com>
> CC: Bjorn Andersson <bjorn.andersson@sonymobile.com>
> CC: Linus Walleij <linus.walleij@linaro.org>
> Signed-off-by: Pramod Gurav <pramod.gurav@smartplayin.com>

Dropping this one as the gpiochip_remove() patch fixes the
problem.

Yours,
Linus Walleij
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diff mbox

Patch

diff --git a/drivers/pinctrl/qcom/pinctrl-msm.c b/drivers/pinctrl/qcom/pinctrl-msm.c
index f4e4f8f..aa34b5a 100644
--- 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;
 	}