[next] drm/i915/pmu: fix sizeof on attr, should be *attr

Submitted by Colin King on Jan. 12, 2018, 5:36 p.m.

Details

Message ID 20180112173603.28486-1-colin.king@canonical.com
State New
Headers show
Series "drm/i915/pmu: fix sizeof on attr, should be *attr" ( rev: 1 ) in DRI devel

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Commit Message

Colin King Jan. 12, 2018, 5:36 p.m.
From: Colin Ian King <colin.king@canonical.com>

I believe the sizeof(attr) should be in fact sizeof(*attr), fortunately
the current code works because sizeof(struct attribute **) is the same
as sizeof(struct attribute *) for x86.

Detected by CoverityScan, CID#1463854 ("Sizeof not portable")

Fixes: 109ec558370f ("drm/i915/pmu: Only enumerate available counters in sysfs")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
---
 drivers/gpu/drm/i915/i915_pmu.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Patch hide | download patch | download mbox

diff --git a/drivers/gpu/drm/i915/i915_pmu.c b/drivers/gpu/drm/i915/i915_pmu.c
index 95ab5e28f5be..9be4f5201e41 100644
--- a/drivers/gpu/drm/i915/i915_pmu.c
+++ b/drivers/gpu/drm/i915/i915_pmu.c
@@ -794,7 +794,7 @@  create_event_attributes(struct drm_i915_private *i915)
 		goto err_alloc;
 
 	/* Max one pointer of each attribute type plus a termination entry. */
-	attr = kzalloc((count * 2 + 1) * sizeof(attr), GFP_KERNEL);
+	attr = kzalloc((count * 2 + 1) * sizeof(*attr), GFP_KERNEL);
 	if (!attr)
 		goto err_alloc;
 

Comments

Hi,

On 12/01/2018 17:36, Colin King wrote:
> From: Colin Ian King <colin.king@canonical.com>
> 
> I believe the sizeof(attr) should be in fact sizeof(*attr), fortunately
> the current code works because sizeof(struct attribute **) is the same
> as sizeof(struct attribute *) for x86.

Thanks, kbuild also reported it and I just pushed a fix.

Out of curiosity, there are platforms where size of pointer is different 
from the size of a pointer to a pointer?

Regards,

Tvrtko

> 
> Detected by CoverityScan, CID#1463854 ("Sizeof not portable")
> 
> Fixes: 109ec558370f ("drm/i915/pmu: Only enumerate available counters in sysfs")
> Signed-off-by: Colin Ian King <colin.king@canonical.com>
> ---
>   drivers/gpu/drm/i915/i915_pmu.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/i915/i915_pmu.c b/drivers/gpu/drm/i915/i915_pmu.c
> index 95ab5e28f5be..9be4f5201e41 100644
> --- a/drivers/gpu/drm/i915/i915_pmu.c
> +++ b/drivers/gpu/drm/i915/i915_pmu.c
> @@ -794,7 +794,7 @@ create_event_attributes(struct drm_i915_private *i915)
>   		goto err_alloc;
>   
>   	/* Max one pointer of each attribute type plus a termination entry. */
> -	attr = kzalloc((count * 2 + 1) * sizeof(attr), GFP_KERNEL);
> +	attr = kzalloc((count * 2 + 1) * sizeof(*attr), GFP_KERNEL);
>   	if (!attr)
>   		goto err_alloc;
>   
>
On 12/01/18 17:48, Tvrtko Ursulin wrote:
> 
> Hi,
> 
> On 12/01/2018 17:36, Colin King wrote:
>> From: Colin Ian King <colin.king@canonical.com>
>>
>> I believe the sizeof(attr) should be in fact sizeof(*attr), fortunately
>> the current code works because sizeof(struct attribute **) is the same
>> as sizeof(struct attribute *) for x86.
> 
> Thanks, kbuild also reported it and I just pushed a fix.
> 
> Out of curiosity, there are platforms where size of pointer is different
> from the size of a pointer to a pointer?

None that I know of.

> 
> Regards,
> 
> Tvrtko
> 
>>
>> Detected by CoverityScan, CID#1463854 ("Sizeof not portable")
>>
>> Fixes: 109ec558370f ("drm/i915/pmu: Only enumerate available counters
>> in sysfs")
>> Signed-off-by: Colin Ian King <colin.king@canonical.com>
>> ---
>>   drivers/gpu/drm/i915/i915_pmu.c | 2 +-
>>   1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/drivers/gpu/drm/i915/i915_pmu.c
>> b/drivers/gpu/drm/i915/i915_pmu.c
>> index 95ab5e28f5be..9be4f5201e41 100644
>> --- a/drivers/gpu/drm/i915/i915_pmu.c
>> +++ b/drivers/gpu/drm/i915/i915_pmu.c
>> @@ -794,7 +794,7 @@ create_event_attributes(struct drm_i915_private
>> *i915)
>>           goto err_alloc;
>>         /* Max one pointer of each attribute type plus a termination
>> entry. */
>> -    attr = kzalloc((count * 2 + 1) * sizeof(attr), GFP_KERNEL);
>> +    attr = kzalloc((count * 2 + 1) * sizeof(*attr), GFP_KERNEL);
>>       if (!attr)
>>           goto err_alloc;
>>