[PATCH 2/2] drm/amdgpu: fix holding mn_lock while allocating memory

[Chunming Zhou]

在 2018/8/24 20:50, Christian König 写道:
> We can't hold the mn_lock while allocating memory.
if you could add some comments from what you discussed with Michal to 
explain why, it would be better.
With that fixed, Acked-by: Chunming Zhou <david1.zhou at amd.com>

David
>
> Signed-off-by: Christian König <christian.koenig at amd.com>
> ---
>   drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c | 30 +++++++++++++++-----------
>   1 file changed, 18 insertions(+), 12 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
> index 80ad23061f1c..34d18d9dfcbd 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
> @@ -1194,26 +1194,23 @@ static int amdgpu_cs_submit(struct amdgpu_cs_parser *p,
>   
>   	int r;
>   
> +	job = p->job;
> +	p->job = NULL;
> +
> +	r = drm_sched_job_init(&job->base, entity, p->filp);
> +	if (r)
> +		goto error_unlock;
> +
>   	amdgpu_mn_lock(p->mn);
>   	amdgpu_bo_list_for_each_userptr_entry(e, p->bo_list) {
>   		struct amdgpu_bo *bo = e->robj;
>   
>   		if (amdgpu_ttm_tt_userptr_needs_pages(bo->tbo.ttm)) {
> -			amdgpu_mn_unlock(p->mn);
> -			return -ERESTARTSYS;
> +			r = -ERESTARTSYS;
> +			goto error_abort;
>   		}
>   	}
>   
> -	job = p->job;
> -	p->job = NULL;
> -
> -	r = drm_sched_job_init(&job->base, entity, p->filp);
> -	if (r) {
> -		amdgpu_job_free(job);
> -		amdgpu_mn_unlock(p->mn);
> -		return r;
> -	}
> -
>   	job->owner = p->filp;
>   	p->fence = dma_fence_get(&job->base.s_fence->finished);
>   
> @@ -1243,6 +1240,15 @@ static int amdgpu_cs_submit(struct amdgpu_cs_parser *p,
>   	amdgpu_mn_unlock(p->mn);
>   
>   	return 0;
> +
> +error_abort:
> +	dma_fence_put(&job->base.s_fence->finished);
> +	job->base.s_fence = NULL;
> +
> +error_unlock:
> +	amdgpu_job_free(job);
> +	amdgpu_mn_unlock(p->mn);
> +	return r;
>   }
>   
>   int amdgpu_cs_ioctl(struct drm_device *dev, void *data, struct drm_file *filp)