drm/amdgpu: fix error handling in amdgpu_cs_process_fence_dep

We always need to drop the ctx reference and should check
for errors first and then dereference the fence pointer.

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Chunming Zhou <david1.zhou@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
index e069de8..4e4094f 100644 (file)
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
@@ -1044,29 +1044,27 @@ static int amdgpu_cs_process_fence_dep(struct amdgpu_cs_parser *p,
                        return r;
                }
 
-               fence = amdgpu_ctx_get_fence(ctx, entity,
-                                            deps[i].handle);
+               fence = amdgpu_ctx_get_fence(ctx, entity, deps[i].handle);
+               amdgpu_ctx_put(ctx);
+
+               if (IS_ERR(fence))
+                       return PTR_ERR(fence);
+               else if (!fence)
+                       continue;
 
                if (chunk->chunk_id == AMDGPU_CHUNK_ID_SCHEDULED_DEPENDENCIES) {
-                       struct drm_sched_fence *s_fence = to_drm_sched_fence(fence);
+                       struct drm_sched_fence *s_fence;
                        struct dma_fence *old = fence;
 
+                       s_fence = to_drm_sched_fence(fence);
                        fence = dma_fence_get(&s_fence->scheduled);
                        dma_fence_put(old);
                }
 
-               if (IS_ERR(fence)) {
-                       r = PTR_ERR(fence);
-                       amdgpu_ctx_put(ctx);
+               r = amdgpu_sync_fence(p->adev, &p->job->sync, fence, true);
+               dma_fence_put(fence);
+               if (r)
                        return r;
-               } else if (fence) {
-                       r = amdgpu_sync_fence(p->adev, &p->job->sync, fence,
-                                       true);
-                       dma_fence_put(fence);
-                       amdgpu_ctx_put(ctx);
-                       if (r)
-                               return r;
-               }
        }
        return 0;
 }