[Bugfix][Hardware][CPU] Fix broken encoder-decoder CPU runner

.buildkite/run-cpu-test-ppc64le.sh

@@ -18,6 +18,8 @@ source /etc/environment
 docker run -itd --entrypoint /bin/bash -v ~/.cache/huggingface:/root/.cache/huggingface --privileged=true --network host -e HF_TOKEN="$HF_TOKEN" --name cpu-test cpu-test
 
 function cpu_tests() {
+  set -e
+
   # Run basic model test
   docker exec cpu-test bash -c "
     set -e

.buildkite/run-cpu-test.sh

@@ -20,6 +20,8 @@ docker run -itd --entrypoint /bin/bash -v ~/.cache/huggingface:/root/.cache/hugg
  --cpuset-mems=1 --privileged=true --network host -e HF_TOKEN --env VLLM_CPU_KVCACHE_SPACE=4 --shm-size=4g --name cpu-test-avx2 cpu-test-avx2
 
 function cpu_tests() {
+  set -e
+
   # offline inference
   docker exec cpu-test-avx2 bash -c "
     set -e

vllm/worker/cpu_embedding_model_runner.py

@@ -95,6 +95,7 @@ def prepare_model_input(
                                                  model_input.seq_lens)
 
         return dataclasses.replace(model_input,
+                                   virtual_engine=virtual_engine,
                                    pooling_metadata=pooling_metadata)
 
     def _prepare_pooling(

vllm/worker/cpu_enc_dec_model_runner.py

@@ -4,6 +4,7 @@
 import torch
 
 from vllm.attention import AttentionMetadata
+from vllm.model_executor import SamplingMetadata
 from vllm.model_executor.layers.sampler import SamplerOutput
 from vllm.multimodal import MultiModalKwargs
 from vllm.sequence import IntermediateTensors, SequenceGroupMetadata
@@ -96,11 +97,21 @@ def prepare_model_input(
             encoder_input_positions_tensor,
         ) = self._prepare_encoder_model_input_tensors(seq_group_metadata_list,
                                                       model_input)
+        # Sampling metadata is only required for the final pp group
+        generators = self.get_generators(finished_requests_ids)
+        sampling_metadata = SamplingMetadata.prepare(seq_group_metadata_list,
+                                                     model_input.seq_lens,
+                                                     model_input.query_lens,
+                                                     self.device,
+                                                     pin_memory=False,
+                                                     generators=generators)
         return dataclasses.replace(
             model_input,
+            sampling_metadata=sampling_metadata,
             attn_metadata=attn_metadata,
             encoder_input_tokens=encoder_input_tokens_tensor,
             encoder_input_positions=encoder_input_positions_tensor,
+            virtual_engine=virtual_engine,
         )
 
     def _prepare_encoder_model_input_tensors(