diff mbox

[04/19] v4l: omap3isp: fix handling platform_get_irq result

Message ID 1443103227-25612-5-git-send-email-a.hajda@samsung.com (mailing list archive)
State Changes Requested, archived
Delegated to: Laurent Pinchart
Headers

Commit Message

Andrzej Hajda Sept. 24, 2015, 2 p.m. UTC 
  The function can return negative value.

The problem has been detected using proposed semantic patch
scripts/coccinelle/tests/assign_signed_to_unsigned.cocci [1].

[1]: http://permalink.gmane.org/gmane.linux.kernel/2046107

Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
---
Hi,

To avoid problems with too many mail recipients I have sent whole
patchset only to LKML. Anyway patches have no dependencies.

Regards
Andrzej
---
 drivers/media/platform/omap3isp/isp.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

Comments

Laurent Pinchart Nov. 9, 2015, 8:16 p.m. UTC | #1 
Hi Andrzej,

Thank you for the patch.

On Thursday 24 September 2015 16:00:12 Andrzej Hajda wrote:
> The function can return negative value.
> 
> The problem has been detected using proposed semantic patch
> scripts/coccinelle/tests/assign_signed_to_unsigned.cocci [1].
> 
> [1]: http://permalink.gmane.org/gmane.linux.kernel/2046107
> 
> Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
> ---
> Hi,
> 
> To avoid problems with too many mail recipients I have sent whole
> patchset only to LKML. Anyway patches have no dependencies.
> 
> Regards
> Andrzej
> ---
>  drivers/media/platform/omap3isp/isp.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/media/platform/omap3isp/isp.c
> b/drivers/media/platform/omap3isp/isp.c index 56e683b..df9d2c2 100644
> --- a/drivers/media/platform/omap3isp/isp.c
> +++ b/drivers/media/platform/omap3isp/isp.c
> @@ -2442,12 +2442,13 @@ static int isp_probe(struct platform_device *pdev)
>  	}
> 
>  	/* Interrupt */
> -	isp->irq_num = platform_get_irq(pdev, 0);
> -	if (isp->irq_num <= 0) {
> +	ret = platform_get_irq(pdev, 0);
> +	if (ret <= 0) {

Looking at platform_get_irq() all error values are negative. You could just 
test for ret < 0 here, and remove the ret = -ENODEV assignment below to keep 
the error code returned by platform_get_irq().

If you're fine with that modification there's no need to resubmit, just let me 
know and I'll fix it when applying it to my tree.

>  		dev_err(isp->dev, "No IRQ resource\n");
>  		ret = -ENODEV;
>  		goto error_iommu;
>  	}
> +	isp->irq_num = ret;
> 
>  	if (devm_request_irq(isp->dev, isp->irq_num, isp_isr, IRQF_SHARED,
>  			     "OMAP3 ISP", isp)) {
Andrzej Hajda Nov. 10, 2015, 6:48 a.m. UTC | #2 
On 11/09/2015 09:16 PM, Laurent Pinchart wrote:
> Hi Andrzej,
>
> Thank you for the patch.
>
> On Thursday 24 September 2015 16:00:12 Andrzej Hajda wrote:
>> The function can return negative value.
>>
>> The problem has been detected using proposed semantic patch
>> scripts/coccinelle/tests/assign_signed_to_unsigned.cocci [1].
>>
>> [1]: http://permalink.gmane.org/gmane.linux.kernel/2046107
>>
>> Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
>> ---
>> Hi,
>>
>> To avoid problems with too many mail recipients I have sent whole
>> patchset only to LKML. Anyway patches have no dependencies.
>>
>> Regards
>> Andrzej
>> ---
>>  drivers/media/platform/omap3isp/isp.c | 5 +++--
>>  1 file changed, 3 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/media/platform/omap3isp/isp.c
>> b/drivers/media/platform/omap3isp/isp.c index 56e683b..df9d2c2 100644
>> --- a/drivers/media/platform/omap3isp/isp.c
>> +++ b/drivers/media/platform/omap3isp/isp.c
>> @@ -2442,12 +2442,13 @@ static int isp_probe(struct platform_device *pdev)
>>  	}
>>
>>  	/* Interrupt */
>> -	isp->irq_num = platform_get_irq(pdev, 0);
>> -	if (isp->irq_num <= 0) {
>> +	ret = platform_get_irq(pdev, 0);
>> +	if (ret <= 0) {
> Looking at platform_get_irq() all error values are negative. You could just 
> test for ret < 0 here, and remove the ret = -ENODEV assignment below to keep 
> the error code returned by platform_get_irq().
>
> If you're fine with that modification there's no need to resubmit, just let me 
> know and I'll fix it when applying it to my tree.

I left it as before, as it was not related to the patch. Additionally I have
lurked little bit inside platform_get_irq and it looks little bit scary to me:
platform_get_irq returns value of of_irq_get if ret >= 0,
of_irq_get calls of_irq_parse_one which can return 0,
in such case irq_create_of_mapping value is returned which is unsigned int
and evaluates to 0 in case of failures.
I am not sure if above scenario can ever occur, but the code looks so messy to me,
that I gave up :)

Anyway if you are sure about your change I am OK with it also :)

Regards
Andrzej

>
>>  		dev_err(isp->dev, "No IRQ resource\n");
>>  		ret = -ENODEV;
>>  		goto error_iommu;
>>  	}
>> +	isp->irq_num = ret;
>>
>>  	if (devm_request_irq(isp->dev, isp->irq_num, isp_isr, IRQF_SHARED,
>>  			     "OMAP3 ISP", isp)) {

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Laurent Pinchart Nov. 10, 2015, 8:53 a.m. UTC | #3 
Hi Andrzej,

On Tuesday 10 November 2015 07:48:54 Andrzej Hajda wrote:
> On 11/09/2015 09:16 PM, Laurent Pinchart wrote:
> > On Thursday 24 September 2015 16:00:12 Andrzej Hajda wrote:
> >> The function can return negative value.
> >> 
> >> The problem has been detected using proposed semantic patch
> >> scripts/coccinelle/tests/assign_signed_to_unsigned.cocci [1].
> >> 
> >> [1]: http://permalink.gmane.org/gmane.linux.kernel/2046107
> >> 
> >> Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
> >> ---
> >> Hi,
> >> 
> >> To avoid problems with too many mail recipients I have sent whole
> >> patchset only to LKML. Anyway patches have no dependencies.
> >> 
> >>  drivers/media/platform/omap3isp/isp.c | 5 +++--
> >>  1 file changed, 3 insertions(+), 2 deletions(-)
> >> 
> >> diff --git a/drivers/media/platform/omap3isp/isp.c
> >> b/drivers/media/platform/omap3isp/isp.c index 56e683b..df9d2c2 100644
> >> --- a/drivers/media/platform/omap3isp/isp.c
> >> +++ b/drivers/media/platform/omap3isp/isp.c
> >> @@ -2442,12 +2442,13 @@ static int isp_probe(struct platform_device
> >> *pdev)
> >>  	}
> >>  	
> >>  	/* Interrupt */
> >> -	isp->irq_num = platform_get_irq(pdev, 0);
> >> -	if (isp->irq_num <= 0) {
> >> +	ret = platform_get_irq(pdev, 0);
> >> +	if (ret <= 0) {
> > 
> > Looking at platform_get_irq() all error values are negative. You could
> > just test for ret < 0 here, and remove the ret = -ENODEV assignment below
> > to keep the error code returned by platform_get_irq().
> > 
> > If you're fine with that modification there's no need to resubmit, just
> > let me know and I'll fix it when applying it to my tree.
> 
> I left it as before, as it was not related to the patch. Additionally I have
> lurked little bit inside platform_get_irq and it looks little bit scary to
> me: platform_get_irq returns value of of_irq_get if ret >= 0,
> of_irq_get calls of_irq_parse_one which can return 0,
> in such case irq_create_of_mapping value is returned which is unsigned int
> and evaluates to 0 in case of failures.
> I am not sure if above scenario can ever occur, but the code looks so messy
> to me, that I gave up :)
> 
> Anyway if you are sure about your change I am OK with it also :)

You're right, that's indeed an issue. It looks like a 0 irq is valid or 
invalid depending on who you ask. NO_IRQ is defined differently depending on 
the architecture :-/ I'll thus keep your version of the patch.

Nonetheless, the core issue should be fixed. Do you feel adventurous ? :-)

> >>  		dev_err(isp->dev, "No IRQ resource\n");
> >>  		ret = -ENODEV;
> >>  		goto error_iommu;
> >>  	
> >>  	}
> >> 
> >> +	isp->irq_num = ret;
> >> 
> >>  	if (devm_request_irq(isp->dev, isp->irq_num, isp_isr, IRQF_SHARED,
> >>  	
> >>  			     "OMAP3 ISP", isp)) {
Andrzej Hajda Nov. 10, 2015, 9:59 a.m. UTC | #4 
On 11/10/2015 09:53 AM, Laurent Pinchart wrote:
> Hi Andrzej,
>
> On Tuesday 10 November 2015 07:48:54 Andrzej Hajda wrote:
>> On 11/09/2015 09:16 PM, Laurent Pinchart wrote:
>>> On Thursday 24 September 2015 16:00:12 Andrzej Hajda wrote:
>>>> The function can return negative value.
>>>>
>>>> The problem has been detected using proposed semantic patch
>>>> scripts/coccinelle/tests/assign_signed_to_unsigned.cocci [1].
>>>>
>>>> [1]: http://permalink.gmane.org/gmane.linux.kernel/2046107
>>>>
>>>> Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
>>>> ---
>>>> Hi,
>>>>
>>>> To avoid problems with too many mail recipients I have sent whole
>>>> patchset only to LKML. Anyway patches have no dependencies.
>>>>
>>>>  drivers/media/platform/omap3isp/isp.c | 5 +++--
>>>>  1 file changed, 3 insertions(+), 2 deletions(-)
>>>>
>>>> diff --git a/drivers/media/platform/omap3isp/isp.c
>>>> b/drivers/media/platform/omap3isp/isp.c index 56e683b..df9d2c2 100644
>>>> --- a/drivers/media/platform/omap3isp/isp.c
>>>> +++ b/drivers/media/platform/omap3isp/isp.c
>>>> @@ -2442,12 +2442,13 @@ static int isp_probe(struct platform_device
>>>> *pdev)
>>>>  	}
>>>>  	
>>>>  	/* Interrupt */
>>>> -	isp->irq_num = platform_get_irq(pdev, 0);
>>>> -	if (isp->irq_num <= 0) {
>>>> +	ret = platform_get_irq(pdev, 0);
>>>> +	if (ret <= 0) {
>>> Looking at platform_get_irq() all error values are negative. You could
>>> just test for ret < 0 here, and remove the ret = -ENODEV assignment below
>>> to keep the error code returned by platform_get_irq().
>>>
>>> If you're fine with that modification there's no need to resubmit, just
>>> let me know and I'll fix it when applying it to my tree.
>> I left it as before, as it was not related to the patch. Additionally I have
>> lurked little bit inside platform_get_irq and it looks little bit scary to
>> me: platform_get_irq returns value of of_irq_get if ret >= 0,
>> of_irq_get calls of_irq_parse_one which can return 0,
>> in such case irq_create_of_mapping value is returned which is unsigned int
>> and evaluates to 0 in case of failures.
>> I am not sure if above scenario can ever occur, but the code looks so messy
>> to me, that I gave up :)
>>
>> Anyway if you are sure about your change I am OK with it also :)
> You're right, that's indeed an issue. It looks like a 0 irq is valid or 
> invalid depending on who you ask. NO_IRQ is defined differently depending on 
> the architecture :-/ I'll thus keep your version of the patch.
>
> Nonetheless, the core issue should be fixed. Do you feel adventurous ? :-)

Currently I am busy with other tasks, so I will be happy if somebody will
take care of it :), if not I will return to it if time permits.

Regards
Andrzej

>
>>>>  		dev_err(isp->dev, "No IRQ resource\n");
>>>>  		ret = -ENODEV;
>>>>  		goto error_iommu;
>>>>  	
>>>>  	}
>>>>
>>>> +	isp->irq_num = ret;
>>>>
>>>>  	if (devm_request_irq(isp->dev, isp->irq_num, isp_isr, IRQF_SHARED,
>>>>  	
>>>>  			     "OMAP3 ISP", isp)) {

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diff mbox

Patch

diff --git a/drivers/media/platform/omap3isp/isp.c b/drivers/media/platform/omap3isp/isp.c
index 56e683b..df9d2c2 100644
--- a/drivers/media/platform/omap3isp/isp.c
+++ b/drivers/media/platform/omap3isp/isp.c
@@ -2442,12 +2442,13 @@  static int isp_probe(struct platform_device *pdev)
 	}
 
 	/* Interrupt */
-	isp->irq_num = platform_get_irq(pdev, 0);
-	if (isp->irq_num <= 0) {
+	ret = platform_get_irq(pdev, 0);
+	if (ret <= 0) {
 		dev_err(isp->dev, "No IRQ resource\n");
 		ret = -ENODEV;
 		goto error_iommu;
 	}
+	isp->irq_num = ret;
 
 	if (devm_request_irq(isp->dev, isp->irq_num, isp_isr, IRQF_SHARED,
 			     "OMAP3 ISP", isp)) {