Repository: huggingface/transformers
Pull request: Fix regression in mllama vision encoder

# What does this PR do?

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- Related issue: https://github.com/vllm-project/vllm/issues/22559
- #39643 introduced a regression on mllama because incorrect vision encoder implementation
- This PR correct `all_intermediate_hidden_states` used in vision encoder to fix it


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- text models: @ArthurZucker
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Changed files:
filename: src/transformers/models/mllama/modeling_mllama.py
patch: @@ -351,13 +351,15 @@ def forward(
                 [What are attention masks?](../glossary#attention-mask)
 
         """
+        encoder_states = ()
         for encoder_layer in self.layers:
             hidden_states = encoder_layer(
                 hidden_state=hidden_states,
                 attention_mask=attention_mask,
             )
+            encoder_states = encoder_states + (hidden_states,)
 
-        return BaseModelOutput(last_hidden_state=hidden_states)
+        return BaseModelOutput(last_hidden_state=hidden_states, hidden_states=encoder_states)
 
 
 # Copied from transformers.models.llama.modeling_llama.LlamaRMSNorm with Llama->MllamaText
@@ -1113,7 +1115,7 @@ def forward(
         hidden_state = hidden_state.reshape(batch_size, num_concurrent_media, num_tiles, num_patches, dim)
 
         # Collect intermediate layer outputs from encoder output
-        all_intermediate_hidden_states = [output.last_hidden_state for _ in self.intermediate_layers_indices]
+        all_intermediate_hidden_states = [output.hidden_states[i] for i in self.intermediate_layers_indices]
         intermediate_hidden_states = torch.stack(all_intermediate_hidden_states, dim=-1)
 
         # Remove padding from intermediate hidden states