Am 10.06.22 um 09:20 schrieb Wan Jiabing:
> Fix following coccicheck warning:
> ./drivers/dma-buf/st-dma-fence-unwrap.c:75:39-45: ERROR: reference preceded by free on line 70
>
> Use 'struct dma_fence *' instead of 'typeof(*fences)' to avoid this
> warning and also fix other 'typeof(*fences)' to make them consistent.
Well that doesn't looks correct to me.
*fence should be valid at this point, why does coccicheck things it is
freed?
Regards,
Christian.
>
> Fixes: 0c5064fa8d5a ("dma-buf: cleanup dma_fence_unwrap selftest v2")
> Signed-off-by: Wan Jiabing <[email protected]>
> ---
> drivers/dma-buf/st-dma-fence-unwrap.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/dma-buf/st-dma-fence-unwrap.c b/drivers/dma-buf/st-dma-fence-unwrap.c
> index 4105d5ea8dde..1137a6d90b32 100644
> --- a/drivers/dma-buf/st-dma-fence-unwrap.c
> +++ b/drivers/dma-buf/st-dma-fence-unwrap.c
> @@ -56,7 +56,7 @@ static struct dma_fence *mock_array(unsigned int num_fences, ...)
>
> va_start(valist, num_fences);
> for (i = 0; i < num_fences; ++i)
> - fences[i] = va_arg(valist, typeof(*fences));
> + fences[i] = va_arg(valist, struct dma_fence *);
> va_end(valist);
>
> array = dma_fence_array_create(num_fences, fences,
> @@ -72,7 +72,7 @@ static struct dma_fence *mock_array(unsigned int num_fences, ...)
> error_put:
> va_start(valist, num_fences);
> for (i = 0; i < num_fences; ++i)
> - dma_fence_put(va_arg(valist, typeof(*fences)));
> + dma_fence_put(va_arg(valist, struct dma_fence *));
> va_end(valist);
> return NULL;
> }
On 2022/6/10 15:24, Christian König wrote:
> Am 10.06.22 um 09:20 schrieb Wan Jiabing:
>> Fix following coccicheck warning:
>> ./drivers/dma-buf/st-dma-fence-unwrap.c:75:39-45: ERROR: reference
>> preceded by free on line 70
>>
>> Use 'struct dma_fence *' instead of 'typeof(*fences)' to avoid this
>> warning and also fix other 'typeof(*fences)' to make them consistent.
>
> Well that doesn't looks correct to me.
>
> *fence should be valid at this point, why does coccicheck things it is
> freed?
*fence is valid. Coccicheck reports this because fence is freed.
But use 'struct dma_fence *' can avoid this wrong report.
I also grep all code and find it's unusual to use 'typeof' in va_arg,
only two files.
grep -R "va_arg(" . | grep 'typeof'
./drivers/dma-buf/st-dma-fence-unwrap.c: fences[i] =
va_arg(valist, typeof(*fences));
./drivers/dma-buf/st-dma-fence-unwrap.c: dma_fence_put(va_arg(valist,
typeof(*fences)));
./lib/test_scanf.c: typeof(*expect) got = *va_arg(ap,
typeof(expect)); \
And other files all use declaration name directly.
So I send this patch makes code clearer and fix the wrong warning by the
way.
Thanks,
Wan Jiabing
>
> Regards,
> Christian.
>
>>
>> Fixes: 0c5064fa8d5a ("dma-buf: cleanup dma_fence_unwrap selftest v2")
>> Signed-off-by: Wan Jiabing <[email protected]>
>> ---
>> drivers/dma-buf/st-dma-fence-unwrap.c | 4 ++--
>> 1 file changed, 2 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/dma-buf/st-dma-fence-unwrap.c
>> b/drivers/dma-buf/st-dma-fence-unwrap.c
>> index 4105d5ea8dde..1137a6d90b32 100644
>> --- a/drivers/dma-buf/st-dma-fence-unwrap.c
>> +++ b/drivers/dma-buf/st-dma-fence-unwrap.c
>> @@ -56,7 +56,7 @@ static struct dma_fence *mock_array(unsigned int
>> num_fences, ...)
>> va_start(valist, num_fences);
>> for (i = 0; i < num_fences; ++i)
>> - fences[i] = va_arg(valist, typeof(*fences));
>> + fences[i] = va_arg(valist, struct dma_fence *);
>> va_end(valist);
>> array = dma_fence_array_create(num_fences, fences,
>> @@ -72,7 +72,7 @@ static struct dma_fence *mock_array(unsigned int
>> num_fences, ...)
>> error_put:
>> va_start(valist, num_fences);
>> for (i = 0; i < num_fences; ++i)
>> - dma_fence_put(va_arg(valist, typeof(*fences)));
>> + dma_fence_put(va_arg(valist, struct dma_fence *));
>> va_end(valist);
>> return NULL;
>> }
>
Am 10.06.22 um 09:52 schrieb Jiabing Wan:
>
>
> On 2022/6/10 15:24, Christian König wrote:
>> Am 10.06.22 um 09:20 schrieb Wan Jiabing:
>>> Fix following coccicheck warning:
>>> ./drivers/dma-buf/st-dma-fence-unwrap.c:75:39-45: ERROR: reference
>>> preceded by free on line 70
>>>
>>> Use 'struct dma_fence *' instead of 'typeof(*fences)' to avoid this
>>> warning and also fix other 'typeof(*fences)' to make them consistent.
>>
>> Well that doesn't looks correct to me.
>>
>> *fence should be valid at this point, why does coccicheck things it
>> is freed?
>
> *fence is valid. Coccicheck reports this because fence is freed.
> But use 'struct dma_fence *' can avoid this wrong report.
Well in this case that's just a clear NAK.
Using typeof(*var) is perfectly valid and preferred should the type
change at some point.
As far as I can see your cocci script is somehow reporting a false warning.
Regards,
Christian.
>
> I also grep all code and find it's unusual to use 'typeof' in va_arg,
> only two files.
>
> grep -R "va_arg(" . | grep 'typeof'
> ./drivers/dma-buf/st-dma-fence-unwrap.c: fences[i] =
> va_arg(valist, typeof(*fences));
> ./drivers/dma-buf/st-dma-fence-unwrap.c: dma_fence_put(va_arg(valist,
> typeof(*fences)));
> ./lib/test_scanf.c: typeof(*expect) got = *va_arg(ap,
> typeof(expect)); \
>
> And other files all use declaration name directly.
> So I send this patch makes code clearer and fix the wrong warning by
> the way.
>
> Thanks,
> Wan Jiabing
>
>>
>> Regards,
>> Christian.
>>
>>>
>>> Fixes: 0c5064fa8d5a ("dma-buf: cleanup dma_fence_unwrap selftest v2")
>>> Signed-off-by: Wan Jiabing <[email protected]>
>>> ---
>>> drivers/dma-buf/st-dma-fence-unwrap.c | 4 ++--
>>> 1 file changed, 2 insertions(+), 2 deletions(-)
>>>
>>> diff --git a/drivers/dma-buf/st-dma-fence-unwrap.c
>>> b/drivers/dma-buf/st-dma-fence-unwrap.c
>>> index 4105d5ea8dde..1137a6d90b32 100644
>>> --- a/drivers/dma-buf/st-dma-fence-unwrap.c
>>> +++ b/drivers/dma-buf/st-dma-fence-unwrap.c
>>> @@ -56,7 +56,7 @@ static struct dma_fence *mock_array(unsigned int
>>> num_fences, ...)
>>> va_start(valist, num_fences);
>>> for (i = 0; i < num_fences; ++i)
>>> - fences[i] = va_arg(valist, typeof(*fences));
>>> + fences[i] = va_arg(valist, struct dma_fence *);
>>> va_end(valist);
>>> array = dma_fence_array_create(num_fences, fences,
>>> @@ -72,7 +72,7 @@ static struct dma_fence *mock_array(unsigned int
>>> num_fences, ...)
>>> error_put:
>>> va_start(valist, num_fences);
>>> for (i = 0; i < num_fences; ++i)
>>> - dma_fence_put(va_arg(valist, typeof(*fences)));
>>> + dma_fence_put(va_arg(valist, struct dma_fence *));
>>> va_end(valist);
>>> return NULL;
>>> }
>>
>