Re: [PATCH AUTOSEL 5.13 001/189] drm/etnaviv: fix NULL check before some freeing functions is not needed

Christian König
2021-07-07T11:50:33Z

Am 07.07.21 um 12:52 schrieb Lucas Stach:
> Am Dienstag, dem 06.07.2021 um 07:11 -0400 schrieb Sasha Levin:
>> From: Tian Tao <tiantao6@hisilicon.com>
>>
>> [ Upstream commit 7d614ab2f20503ed8766363d41f8607337571adf ]
>>
>> fixed the below warning:
>> drivers/gpu/drm/etnaviv/etnaviv_gem_prime.c:84:2-8: WARNING: NULL check
>> before some freeing functions is not needed.
> While the subject contains "fix" this only removes a duplicated NULL
> check, so the code is correct before and after this change.
> Is this really stable material? Doesn't this just add commit noise to
> the stable kernels?

Yeah, agree.

I also had a case where a NULL check was removed in amdgpu and then a
bit later back ported to stable.

Maybe just use something like "remove superfluous NULL check".

Regards,
Christian.

>
> Regards,
> Lucas
>
>> Signed-off-by: Tian Tao <tiantao6@hisilicon.com>
>> Acked-by: Christian König <christian.koenig@amd.com>
>> Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
>> Signed-off-by: Sasha Levin <sashal@kernel.org>
>> ---
>> drivers/gpu/drm/etnaviv/etnaviv_gem_prime.c | 3 +--
>> 1 file changed, 1 insertion(+), 2 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/etnaviv/etnaviv_gem_prime.c b/drivers/gpu/drm/etnaviv/etnaviv_gem_prime.c
>> index b390dd4d60b7..d741b1d735f7 100644
>> --- a/drivers/gpu/drm/etnaviv/etnaviv_gem_prime.c
>> +++ b/drivers/gpu/drm/etnaviv/etnaviv_gem_prime.c
>> @@ -80,8 +80,7 @@ static void etnaviv_gem_prime_release(struct etnaviv_gem_object *etnaviv_obj)
>> /* Don't drop the pages for imported dmabuf, as they are not
>> * ours, just free the array we allocated:
>> */
>> - if (etnaviv_obj->pages)
>> - kvfree(etnaviv_obj->pages);
>> + kvfree(etnaviv_obj->pages);
>>
>> drm_prime_gem_destroy(&etnaviv_obj->base, etnaviv_obj->sgt);
>> }
>