diff --git a/src/diffusers/loaders/lora_pipeline.py b/src/diffusers/loaders/lora_pipeline.py index b85f51db83bc..10b6a8f02710 100644 --- a/src/diffusers/loaders/lora_pipeline.py +++ b/src/diffusers/loaders/lora_pipeline.py @@ -4813,22 +4813,43 @@ def _maybe_expand_t2v_lora_for_i2v( if transformer.config.image_dim is None: return state_dict + target_device = transformer.device + if any(k.startswith("transformer.blocks.") for k in state_dict): - num_blocks = len({k.split("blocks.")[1].split(".")[0] for k in state_dict}) + num_blocks = len({k.split("blocks.")[1].split(".")[0] for k in state_dict if "blocks." in k}) is_i2v_lora = any("add_k_proj" in k for k in state_dict) and any("add_v_proj" in k for k in state_dict) + has_bias = any(".lora_B.bias" in k for k in state_dict) if is_i2v_lora: return state_dict for i in range(num_blocks): for o, c in zip(["k_img", "v_img"], ["add_k_proj", "add_v_proj"]): + # These keys should exist if the block `i` was part of the T2V LoRA. + ref_key_lora_A = f"transformer.blocks.{i}.attn2.to_k.lora_A.weight" + ref_key_lora_B = f"transformer.blocks.{i}.attn2.to_k.lora_B.weight" + + if ref_key_lora_A not in state_dict or ref_key_lora_B not in state_dict: + continue + state_dict[f"transformer.blocks.{i}.attn2.{c}.lora_A.weight"] = torch.zeros_like( - state_dict[f"transformer.blocks.{i}.attn2.to_k.lora_A.weight"] + state_dict[f"transformer.blocks.{i}.attn2.to_k.lora_A.weight"], device=target_device ) state_dict[f"transformer.blocks.{i}.attn2.{c}.lora_B.weight"] = torch.zeros_like( - state_dict[f"transformer.blocks.{i}.attn2.to_k.lora_B.weight"] + state_dict[f"transformer.blocks.{i}.attn2.to_k.lora_B.weight"], device=target_device ) + # If the original LoRA had biases (indicated by has_bias) + # AND the specific reference bias key exists for this block. + + ref_key_lora_B_bias = f"transformer.blocks.{i}.attn2.to_k.lora_B.bias" + if has_bias and ref_key_lora_B_bias in state_dict: + ref_lora_B_bias_tensor = state_dict[ref_key_lora_B_bias] + state_dict[f"transformer.blocks.{i}.attn2.{c}.lora_B.bias"] = torch.zeros_like( + ref_lora_B_bias_tensor, + device=target_device, + ) + return state_dict def load_lora_weights(