drm/amdgpu: Reserve space for shared fence

Call reservation_object_reserve_shared to reserve
space for shared fence. Otherwise it will trigger
BUG_ON condition in reservation_object_add_shared_fence.
Signed-off-by: Oak Zeng <Oak.Zeng@amd.com>
Acked-by: Christian Konig <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c

@@ -2152,12 +2152,16 @@ int amdgpu_amdkfd_add_gws_to_process(void *info, void *gws, struct kgd_mem **mem
 	 * Add process eviction fence to bo so they can
 	 * evict each other.
 	 */
+	ret = reservation_object_reserve_shared(gws_bo->tbo.resv, 1);
+	if (ret)
+		goto reserve_shared_fail;
 	amdgpu_bo_fence(gws_bo, &process_info->eviction_fence->base, true);
 	amdgpu_bo_unreserve(gws_bo);
 	mutex_unlock(&(*mem)->process_info->lock);
 
 	return ret;
 
+reserve_shared_fail:
 bo_validation_failure:
 	amdgpu_bo_unreserve(gws_bo);
 bo_reservation_failure: