[PATCH] drm/amdgpu: fix memory leak in wait_all_fence

[Christian König]

Am 07.04.2017 um 05:36 schrieb Chunming Zhou:
> Change-Id: Ib3e271e00e49f10152c1b3eace981a6bf78820de
> Signed-off-by: Chunming Zhou <David1.Zhou at amd.com>

NAK, that will allocate an array for the fence again, which we wanted to 
avoid.

We should just drop the fence reference directly after waiting for it.

Regards,
Christian.

> ---
>   drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c | 25 +++++++++++++++++++------
>   1 file changed, 19 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
> index de1c4c3..d842452 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
> @@ -1216,22 +1216,28 @@ static int amdgpu_cs_wait_all_fences(struct amdgpu_device *adev,
>   				     struct drm_amdgpu_fence *fences)
>   {
>   	uint32_t fence_count = wait->in.fence_count;
> +	struct fence **array;
>   	unsigned int i;
>   	long r = 1;
>   
> +	array = kcalloc(fence_count, sizeof(struct fence *), GFP_KERNEL);
> +
> +	if (array == NULL)
> +		return -ENOMEM;
>   	for (i = 0; i < fence_count; i++) {
>   		struct fence *fence;
>   		unsigned long timeout = amdgpu_gem_timeout(wait->in.timeout_ns);
>   
>   		fence = amdgpu_cs_get_fence(adev, filp, &fences[i]);
> -		if (IS_ERR(fence))
> -			return PTR_ERR(fence);
> -		else if (!fence)
> +		if (IS_ERR(fence)) {
> +			r = PTR_ERR(fence);
> +			goto err;
> +		} else if (!fence)
>   			continue;
> -
> +		array[i] = fence;
>   		r = kcl_fence_wait_timeout(fence, true, timeout);
>   		if (r < 0)
> -			return r;
> +			goto err;
>   
>   		if (r == 0)
>   			break;
> @@ -1240,7 +1246,14 @@ static int amdgpu_cs_wait_all_fences(struct amdgpu_device *adev,
>   	memset(wait, 0, sizeof(*wait));
>   	wait->out.status = (r > 0);
>   
> -	return 0;
> +	r = 0;
> +
> +err:
> +	for (i = 0; i < fence_count; i++)
> +		fence_put(array[i]);
> +	kfree(array);
> +
> +	return r;
>   }
>   
>   /**