vllm - 💡(How to fix) Fix [Bug]:CUDA illegal instruction during decode (V1 Engine + NVFP4) on aarch64 (NVIDIA GB10) [3 comments, 2 participants]

Official PRs (…)
ON THIS PAGE

GitHub issue graph ai analysis

Paste a GitHub issue URL. We fetch that issue, discover linked issues from bodies/comments/timeline, collect linked pull requests, and produce a structured English report.

The report is written in English Markdown for sharing and archival.

Helpful · Quick feedback

Loading…
GitHub stats
vllm-project/vllm#39761Fetched 2026-04-16 06:36:53
View on GitHub
Comments
3
Participants
2
Timeline
10
Reactions
0
Author
Participants
Timeline (top)
commented ×3subscribed ×3mentioned ×2labeled ×1

Error Message

When running an NVFP4 quantized MoE model (qwen3.5-35b-a3b-nvfp4) on an ARM64 server equipped with an NVIDIA GB10 (Grace Blackwell) GPU (which natively supports NVFP4), the vLLM V1 engine crashes with a torch.AcceleratorError: CUDA error: an illegal instruction was encountered. (EngineCore pid=166) ERROR 04-14 02:42:14 [dump_input.py:72] Dumping input data for V1 LLM engine (v0.19.1rc1.dev203+g0f3ce4c74) with config: model='/workspace/models/qwen3.5-35b-a3b-nvfp4', speculative_config=None, tokenizer='/workspace/models/qwen3.5-35b-a3b-nvfp4', skip_tokenizer_init=False, tokenizer_mode=auto, revision=None, tokenizer_revision=None, trust_remote_code=False, dtype=torch.bfloat16, max_seq_len=131072, download_dir=None, load_format=auto, tensor_parallel_size=1, pipeline_parallel_size=1, data_parallel_size=1, decode_context_parallel_size=1, dcp_comm_backend=ag_rs, disable_custom_all_reduce=False, quantization=compressed-tensors, quantization_config=None, enforce_eager=False, enable_return_routed_experts=False, kv_cache_dtype=auto, device_config=cuda, structured_outputs_config=StructuredOutputsConfig(backend='auto', disable_any_whitespace=False, disable_additional_properties=False, reasoning_parser='qwen3', reasoning_parser_plugin='', enable_in_reasoning=False), observability_config=ObservabilityConfig(show_hidden_metrics_for_version=None, otlp_traces_endpoint=None, collect_detailed_traces=None, kv_cache_metrics=False, kv_cache_metrics_sample=0.01, cudagraph_metrics=False, enable_layerwise_nvtx_tracing=False, enable_mfu_metrics=False, enable_mm_processor_stats=False, enable_logging_iteration_details=False), seed=0, served_model_name=qwen3.5-35b, enable_prefix_caching=True, enable_chunked_prefill=True, pooler_config=None, compilation_config={'mode': <CompilationMode.VLLM_COMPILE: 3>, 'debug_dump_path': None, 'cache_dir': '/root/.cache/vllm/torch_compile_cache/617ec03b22', 'compile_cache_save_format': 'binary', 'backend': 'inductor', 'custom_ops': ['none'], 'ir_enable_torch_wrap': True, 'splitting_ops': ['vllm::unified_attention_with_output', 'vllm::unified_mla_attention_with_output', 'vllm::mamba_mixer2', 'vllm::mamba_mixer', 'vllm::short_conv', 'vllm::linear_attention', 'vllm::plamo2_mamba_mixer', 'vllm::gdn_attention_core', 'vllm::olmo_hybrid_gdn_full_forward', 'vllm::kda_attention', 'vllm::sparse_attn_indexer', 'vllm::rocm_aiter_sparse_attn_indexer', 'vllm::unified_kv_cache_update', 'vllm::unified_mla_kv_cache_update'], 'compile_mm_encoder': False, 'cudagraph_mm_encoder': False, 'encoder_cudagraph_token_budgets': [], 'encoder_cudagraph_max_images_per_batch': 0, 'compile_sizes': [], 'compile_ranges_endpoints': [8192], 'inductor_compile_config': {'enable_auto_functionalized_v2': False, 'size_asserts': False, 'alignment_asserts': False, 'scalar_asserts': False, 'combo_kernels': True, 'benchmark_combo_kernel': True}, 'inductor_passes': {}, 'cudagraph_mode': <CUDAGraphMode.FULL_AND_PIECEWISE: (2, 1)>, 'cudagraph_num_of_warmups': 1, 'cudagraph_capture_sizes': [1, 2, 4, 8, 16, 24, 32, 40, 48, 56, 64, 72, 80, 88, 96, 104, 112, 120, 128, 136, 144, 152, 160, 168, 176, 184, 192, 200, 208, 216, 224, 232, 240, 248, 256, 272, 288, 304, 320, 336, 352, 368, 384, 400, 416, 432, 448, 464, 480, 496, 512], 'cudagraph_copy_inputs': False, 'cudagraph_specialize_lora': True, 'use_inductor_graph_partition': False, 'pass_config': {'fuse_norm_quant': False, 'fuse_act_quant': True, 'fuse_attn_quant': False, 'enable_sp': False, 'fuse_gemm_comms': False, 'fuse_allreduce_rms': False}, 'max_cudagraph_capture_size': 512, 'dynamic_shapes_config': {'type': <DynamicShapesType.BACKED: 'backed'>, 'evaluate_guards': False, 'assume_32_bit_indexing': False}, 'local_cache_dir': '/root/.cache/vllm/torch_compile_cache/617ec03b22/rank_0_0/backbone', 'fast_moe_cold_start': False, 'static_all_moe_layers': ['language_model.model.layers.0.mlp.experts', 'language_model.model.layers.1.mlp.experts', 'language_model.model.layers.2.mlp.experts', 'language_model.model.layers.3.mlp.experts', 'language_model.model.layers.4.mlp.experts', 'language_model.model.layers.5.mlp.experts', 'language_model.model.layers.6.mlp.experts', 'language_model.model.layers.7.mlp.experts', 'language_model.model.layers.8.mlp.experts', 'language_model.model.layers.9.mlp.experts', 'language_model.model.layers.10.mlp.experts', 'language_model.model.layers.11.mlp.experts', 'language_model.model.layers.12.mlp.experts', 'language_model.model.layers.13.mlp.experts', 'language_model.model.layers.14.mlp.experts', 'language_model.model.layers.15.mlp.experts', 'language_model.model.layers.16.mlp.experts', 'language_model.model.layers.17.mlp.experts', 'language_model.model.layers.18.mlp.experts', 'language_model.model.layers.19.mlp.experts', 'language_model.model.layers.20.mlp.experts', 'language_model.model.layers.21.mlp.experts', 'language_model.model.layers.22.mlp.experts', 'language_model.model.layers.23.mlp.experts', 'language_model.model.layers.24.mlp.experts', 'language_model.model.layers.25.mlp.experts', 'language_model.model.layers.26.mlp.experts', 'language_model.model.layers.27.mlp.experts', 'language_model.model.layers.28.mlp.experts', 'language_model.model.layers.29.mlp.experts', 'language_model.model.layers.30.mlp.experts', 'language_model.model.layers.31.mlp.experts', 'language_model.model.layers.32.mlp.experts', 'language_model.model.layers.33.mlp.experts', 'language_model.model.layers.34.mlp.experts', 'language_model.model.layers.35.mlp.experts', 'language_model.model.layers.36.mlp.experts', 'language_model.model.layers.37.mlp.experts', 'language_model.model.layers.38.mlp.experts', 'language_model.model.layers.39.mlp.experts']}, kernel_config=KernelConfig(ir_op_priority=IrOpPriorityConfig(rms_norm=['native']), enable_flashinfer_autotune=True, moe_backend='auto'), (EngineCore pid=166) ERROR 04-14 02:42:14 [dump_input.py:79] Dumping scheduler output for model execution: SchedulerOutput(scheduled_new_reqs=[], scheduled_cached_reqs=CachedRequestData(req_ids=['chatcmpl-bcfbde213cb28031-bc849a28'],resumed_req_ids=set(),new_token_ids_lens=[],all_token_ids_lens={},new_block_ids=[([5], [6], [7], [8])],num_computed_tokens=[1056],num_output_tokens=[1043]), num_scheduled_tokens={chatcmpl-bcfbde213cb28031-bc849a28: 1}, total_num_scheduled_tokens=1, scheduled_spec_decode_tokens={}, scheduled_encoder_inputs={}, num_common_prefix_blocks=[0, 0, 0, 2], finished_req_ids=[], free_encoder_mm_hashes=[], preempted_req_ids=[], has_structured_output_requests=false, pending_structured_output_tokens=false, num_invalid_spec_tokens=null, kv_connector_metadata=null, ec_connector_metadata=null, new_block_ids_to_zero=[8]) (EngineCore pid=166) ERROR 04-14 02:42:14 [dump_input.py:81] Dumping scheduler stats: SchedulerStats(num_running_reqs=1, num_waiting_reqs=0, step_counter=0, current_wave=0, kv_cache_usage=0.0011814744801512678, encoder_cache_usage=0.0, prefix_cache_stats=PrefixCacheStats(reset=False, requests=0, queries=0, hits=0, preempted_requests=0, preempted_queries=0, preempted_hits=0), connector_prefix_cache_stats=None, kv_cache_eviction_events=[], spec_decoding_stats=None, kv_connector_stats=None, waiting_lora_adapters={}, running_lora_adapters={}, cudagraph_stats=None, perf_stats=None) (EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112] EngineCore encountered a fatal error. (EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112] Traceback (most recent call last): (EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112] File "/usr/local/lib/python3.12/dist-packages/vllm/v1/engine/core.py", line 1103, in run_engine_core (EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112] engine_core.run_busy_loop() (EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112] File "/usr/local/lib/python3.12/dist-packages/vllm/v1/engine/core.py", line 1144, in run_busy_loop (EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112] self._process_engine_step() (EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112] File "/usr/local/lib/python3.12/dist-packages/vllm/v1/engine/core.py", line 1183, in _process_engine_step (EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112] outputs, model_executed = self.step_fn() (EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112] ^^^^^^^^^^^^^^ (EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112] File "/usr/local/lib/python3.12/dist-packages/vllm/v1/engine/core.py", line 501, in step_with_batch_queue (EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112] model_output = future.result() (EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112] ^^^^^^^^^^^^^^^ (EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112] File "/usr/lib/python3.12/concurrent/futures/_base.py", line 456, in result (EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112] return self.__get_result() (EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112] ^^^^^^^^^^^^^^^^^^^ (EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112] File "/usr/lib/python3.12/concurrent/futures/_base.py", line 401, in __get_result (EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112] raise self._exception (EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112] File "/usr/lib/python3.12/concurrent/futures/thread.py", line 59, in run (EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112] result = self.fn(*self.args, **self.kwargs) (EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112] ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ (EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112] File "/usr/local/lib/python3.12/dist-packages/vllm/v1/worker/gpu_model_runner.py", line 266, in get_output (EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112] self.async_copy_ready_event.synchronize() (EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112] torch.AcceleratorError: CUDA error: an illegal instruction was encountered (EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112] Search for `cudaErrorIllegalInstruction' in https://docs.nvidia.com/cuda/cuda-runtime-api/group__CUDART__TYPES.html for more information. (EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112] CUDA kernel errors might be asynchronously reported at some other API call, so the stacktrace below might be incorrect. (EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112] For debugging consider passing CUDA_LAUNCH_BLOCKING=1

Root Cause

(APIServer pid=1) INFO 04-14 02:41:48 [loggers.py:259] Engine 000: Avg prompt throughput: 1.4 tokens/s, Avg generation throughput: 9.3 tokens/s, Running: 1 reqs, Waiting: 0 reqs, GPU KV cache usage: 0.1%, Prefix cache hit rate: 0.0% (APIServer pid=1) INFO 04-14 02:41:58 [loggers.py:259] Engine 000: Avg prompt throughput: 0.0 tokens/s, Avg generation throughput: 36.6 tokens/s, Running: 1 reqs, Waiting: 0 reqs, GPU KV cache usage: 0.1%, Prefix cache hit rate: 0.0% (APIServer pid=1) INFO 04-14 02:42:08 [loggers.py:259] Engine 000: Avg prompt throughput: 0.0 tokens/s, Avg generation throughput: 37.0 tokens/s, Running: 1 reqs, Waiting: 0 reqs, GPU KV cache usage: 0.1%, Prefix cache hit rate: 0.0% (EngineCore pid=166) ERROR 04-14 02:42:14 [dump_input.py:72] Dumping input data for V1 LLM engine (v0.19.1rc1.dev203+g0f3ce4c74) with config: model='/workspace/models/qwen3.5-35b-a3b-nvfp4', speculative_config=None, tokenizer='/workspace/models/qwen3.5-35b-a3b-nvfp4', skip_tokenizer_init=False, tokenizer_mode=auto, revision=None, tokenizer_revision=None, trust_remote_code=False, dtype=torch.bfloat16, max_seq_len=131072, download_dir=None, load_format=auto, tensor_parallel_size=1, pipeline_parallel_size=1, data_parallel_size=1, decode_context_parallel_size=1, dcp_comm_backend=ag_rs, disable_custom_all_reduce=False, quantization=compressed-tensors, quantization_config=None, enforce_eager=False, enable_return_routed_experts=False, kv_cache_dtype=auto, device_config=cuda, structured_outputs_config=StructuredOutputsConfig(backend='auto', disable_any_whitespace=False, disable_additional_properties=False, reasoning_parser='qwen3', reasoning_parser_plugin='', enable_in_reasoning=False), observability_config=ObservabilityConfig(show_hidden_metrics_for_version=None, otlp_traces_endpoint=None, collect_detailed_traces=None, kv_cache_metrics=False, kv_cache_metrics_sample=0.01, cudagraph_metrics=False, enable_layerwise_nvtx_tracing=False, enable_mfu_metrics=False, enable_mm_processor_stats=False, enable_logging_iteration_details=False), seed=0, served_model_name=qwen3.5-35b, enable_prefix_caching=True, enable_chunked_prefill=True, pooler_config=None, compilation_config={'mode': <CompilationMode.VLLM_COMPILE: 3>, 'debug_dump_path': None, 'cache_dir': '/root/.cache/vllm/torch_compile_cache/617ec03b22', 'compile_cache_save_format': 'binary', 'backend': 'inductor', 'custom_ops': ['none'], 'ir_enable_torch_wrap': True, 'splitting_ops': ['vllm::unified_attention_with_output', 'vllm::unified_mla_attention_with_output', 'vllm::mamba_mixer2', 'vllm::mamba_mixer', 'vllm::short_conv', 'vllm::linear_attention', 'vllm::plamo2_mamba_mixer', 'vllm::gdn_attention_core', 'vllm::olmo_hybrid_gdn_full_forward', 'vllm::kda_attention', 'vllm::sparse_attn_indexer', 'vllm::rocm_aiter_sparse_attn_indexer', 'vllm::unified_kv_cache_update', 'vllm::unified_mla_kv_cache_update'], 'compile_mm_encoder': False, 'cudagraph_mm_encoder': False, 'encoder_cudagraph_token_budgets': [], 'encoder_cudagraph_max_images_per_batch': 0, 'compile_sizes': [], 'compile_ranges_endpoints': [8192], 'inductor_compile_config': {'enable_auto_functionalized_v2': False, 'size_asserts': False, 'alignment_asserts': False, 'scalar_asserts': False, 'combo_kernels': True, 'benchmark_combo_kernel': True}, 'inductor_passes': {}, 'cudagraph_mode': <CUDAGraphMode.FULL_AND_PIECEWISE: (2, 1)>, 'cudagraph_num_of_warmups': 1, 'cudagraph_capture_sizes': [1, 2, 4, 8, 16, 24, 32, 40, 48, 56, 64, 72, 80, 88, 96, 104, 112, 120, 128, 136, 144, 152, 160, 168, 176, 184, 192, 200, 208, 216, 224, 232, 240, 248, 256, 272, 288, 304, 320, 336, 352, 368, 384, 400, 416, 432, 448, 464, 480, 496, 512], 'cudagraph_copy_inputs': False, 'cudagraph_specialize_lora': True, 'use_inductor_graph_partition': False, 'pass_config': {'fuse_norm_quant': False, 'fuse_act_quant': True, 'fuse_attn_quant': False, 'enable_sp': False, 'fuse_gemm_comms': False, 'fuse_allreduce_rms': False}, 'max_cudagraph_capture_size': 512, 'dynamic_shapes_config': {'type': <DynamicShapesType.BACKED: 'backed'>, 'evaluate_guards': False, 'assume_32_bit_indexing': False}, 'local_cache_dir': '/root/.cache/vllm/torch_compile_cache/617ec03b22/rank_0_0/backbone', 'fast_moe_cold_start': False, 'static_all_moe_layers': ['language_model.model.layers.0.mlp.experts', 'language_model.model.layers.1.mlp.experts', 'language_model.model.layers.2.mlp.experts', 'language_model.model.layers.3.mlp.experts', 'language_model.model.layers.4.mlp.experts', 'language_model.model.layers.5.mlp.experts', 'language_model.model.layers.6.mlp.experts', 'language_model.model.layers.7.mlp.experts', 'language_model.model.layers.8.mlp.experts', 'language_model.model.layers.9.mlp.experts', 'language_model.model.layers.10.mlp.experts', 'language_model.model.layers.11.mlp.experts', 'language_model.model.layers.12.mlp.experts', 'language_model.model.layers.13.mlp.experts', 'language_model.model.layers.14.mlp.experts', 'language_model.model.layers.15.mlp.experts', 'language_model.model.layers.16.mlp.experts', 'language_model.model.layers.17.mlp.experts', 'language_model.model.layers.18.mlp.experts', 'language_model.model.layers.19.mlp.experts', 'language_model.model.layers.20.mlp.experts', 'language_model.model.layers.21.mlp.experts', 'language_model.model.layers.22.mlp.experts', 'language_model.model.layers.23.mlp.experts', 'language_model.model.layers.24.mlp.experts', 'language_model.model.layers.25.mlp.experts', 'language_model.model.layers.26.mlp.experts', 'language_model.model.layers.27.mlp.experts', 'language_model.model.layers.28.mlp.experts', 'language_model.model.layers.29.mlp.experts', 'language_model.model.layers.30.mlp.experts', 'language_model.model.layers.31.mlp.experts', 'language_model.model.layers.32.mlp.experts', 'language_model.model.layers.33.mlp.experts', 'language_model.model.layers.34.mlp.experts', 'language_model.model.layers.35.mlp.experts', 'language_model.model.layers.36.mlp.experts', 'language_model.model.layers.37.mlp.experts', 'language_model.model.layers.38.mlp.experts', 'language_model.model.layers.39.mlp.experts']}, kernel_config=KernelConfig(ir_op_priority=IrOpPriorityConfig(rms_norm=['native']), enable_flashinfer_autotune=True, moe_backend='auto'), (EngineCore pid=166) ERROR 04-14 02:42:14 [dump_input.py:79] Dumping scheduler output for model execution: SchedulerOutput(scheduled_new_reqs=[], scheduled_cached_reqs=CachedRequestData(req_ids=['chatcmpl-bcfbde213cb28031-bc849a28'],resumed_req_ids=set(),new_token_ids_lens=[],all_token_ids_lens={},new_block_ids=[([5], [6], [7], [8])],num_computed_tokens=[1056],num_output_tokens=[1043]), num_scheduled_tokens={chatcmpl-bcfbde213cb28031-bc849a28: 1}, total_num_scheduled_tokens=1, scheduled_spec_decode_tokens={}, scheduled_encoder_inputs={}, num_common_prefix_blocks=[0, 0, 0, 2], finished_req_ids=[], free_encoder_mm_hashes=[], preempted_req_ids=[], has_structured_output_requests=false, pending_structured_output_tokens=false, num_invalid_spec_tokens=null, kv_connector_metadata=null, ec_connector_metadata=null, new_block_ids_to_zero=[8]) (EngineCore pid=166) ERROR 04-14 02:42:14 [dump_input.py:81] Dumping scheduler stats: SchedulerStats(num_running_reqs=1, num_waiting_reqs=0, step_counter=0, current_wave=0, kv_cache_usage=0.0011814744801512678, encoder_cache_usage=0.0, prefix_cache_stats=PrefixCacheStats(reset=False, requests=0, queries=0, hits=0, preempted_requests=0, preempted_queries=0, preempted_hits=0), connector_prefix_cache_stats=None, kv_cache_eviction_events=[], spec_decoding_stats=None, kv_connector_stats=None, waiting_lora_adapters={}, running_lora_adapters={}, cudagraph_stats=None, perf_stats=None) (EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112] EngineCore encountered a fatal error. (EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112] Traceback (most recent call last): (EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112] File "/usr/local/lib/python3.12/dist-packages/vllm/v1/engine/core.py", line 1103, in run_engine_core (EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112] engine_core.run_busy_loop() (EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112] File "/usr/local/lib/python3.12/dist-packages/vllm/v1/engine/core.py", line 1144, in run_busy_loop (EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112] self._process_engine_step() (EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112] File "/usr/local/lib/python3.12/dist-packages/vllm/v1/engine/core.py", line 1183, in _process_engine_step (EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112] outputs, model_executed = self.step_fn() (EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112] ^^^^^^^^^^^^^^ (EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112] File "/usr/local/lib/python3.12/dist-packages/vllm/v1/engine/core.py", line 501, in step_with_batch_queue (EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112] model_output = future.result() (EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112] ^^^^^^^^^^^^^^^ (EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112] File "/usr/lib/python3.12/concurrent/futures/_base.py", line 456, in result (EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112] return self.__get_result() (EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112] ^^^^^^^^^^^^^^^^^^^ (EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112] File "/usr/lib/python3.12/concurrent/futures/_base.py", line 401, in __get_result (EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112] raise self._exception (EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112] File "/usr/lib/python3.12/concurrent/futures/thread.py", line 59, in run (EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112] result = self.fn(*self.args, **self.kwargs) (EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112] ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ (EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112] File "/usr/local/lib/python3.12/dist-packages/vllm/v1/worker/gpu_model_runner.py", line 266, in get_output (EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112] self.async_copy_ready_event.synchronize() (EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112] torch.AcceleratorError: CUDA error: an illegal instruction was encountered (EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112] Search for cudaErrorIllegalInstruction' in https://docs.nvidia.com/cuda/cuda-runtime-api/group__CUDART__TYPES.html for more information. (EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112] CUDA kernel errors might be asynchronously reported at some other API call, so the stacktrace below might be incorrect. (EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112] For debugging consider passing CUDA_LAUNCH_BLOCKING=1 (EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112] Compile with TORCH_USE_CUDA_DSAto enable device-side assertions. (EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112] (EngineCore pid=166) Process EngineCore: (EngineCore pid=166) Traceback (most recent call last): (EngineCore pid=166) File "/usr/lib/python3.12/multiprocessing/process.py", line 314, in _bootstrap (EngineCore pid=166) self.run() (EngineCore pid=166) File "/usr/lib/python3.12/multiprocessing/process.py", line 108, in run (EngineCore pid=166) self._target(*self._args, **self._kwargs) (EngineCore pid=166) File "/usr/local/lib/python3.12/dist-packages/vllm/v1/engine/core.py", line 1114, in run_engine_core (EngineCore pid=166) raise e (EngineCore pid=166) File "/usr/local/lib/python3.12/dist-packages/vllm/v1/engine/core.py", line 1103, in run_engine_core (EngineCore pid=166) engine_core.run_busy_loop() (EngineCore pid=166) File "/usr/local/lib/python3.12/dist-packages/vllm/v1/engine/core.py", line 1144, in run_busy_loop (EngineCore pid=166) self._process_engine_step() (EngineCore pid=166) File "/usr/local/lib/python3.12/dist-packages/vllm/v1/engine/core.py", line 1183, in _process_engine_step (EngineCore pid=166) outputs, model_executed = self.step_fn() (EngineCore pid=166) ^^^^^^^^^^^^^^ (EngineCore pid=166) File "/usr/local/lib/python3.12/dist-packages/vllm/v1/engine/core.py", line 501, in step_with_batch_queue (EngineCore pid=166) model_output = future.result() (EngineCore pid=166) ^^^^^^^^^^^^^^^ (EngineCore pid=166) File "/usr/lib/python3.12/concurrent/futures/_base.py", line 456, in result (EngineCore pid=166) return self.__get_result() (EngineCore pid=166) ^^^^^^^^^^^^^^^^^^^ (EngineCore pid=166) File "/usr/lib/python3.12/concurrent/futures/_base.py", line 401, in __get_result (EngineCore pid=166) raise self._exception (EngineCore pid=166) File "/usr/lib/python3.12/concurrent/futures/thread.py", line 59, in run (EngineCore pid=166) result = self.fn(*self.args, **self.kwargs) (EngineCore pid=166) ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ (EngineCore pid=166) File "/usr/local/lib/python3.12/dist-packages/vllm/v1/worker/gpu_model_runner.py", line 266, in get_output (EngineCore pid=166) self.async_copy_ready_event.synchronize() (EngineCore pid=166) torch.AcceleratorError: CUDA error: an illegal instruction was encountered (EngineCore pid=166) Search forcudaErrorIllegalInstruction' in https://docs.nvidia.com/cuda/cuda-runtime-api/group__CUDART__TYPES.html for more information. (EngineCore pid=166) CUDA kernel errors might be asynchronously reported at some other API call, so the stacktrace below might be incorrect. (EngineCore pid=166) For debugging consider passing CUDA_LAUNCH_BLOCKING=1 (EngineCore pid=166) Compile with TORCH_USE_CUDA_DSA to enable device-side assertions. (EngineCore pid=166) (APIServer pid=1) ERROR 04-14 02:42:14 [async_llm.py:701] AsyncLLM output_handler failed. (APIServer pid=1) ERROR 04-14 02:42:14 [async_llm.py:701] Traceback (most recent call last): (APIServer pid=1) ERROR 04-14 02:42:14 [async_llm.py:701] File "/usr/local/lib/python3.12/dist-packages/vllm/v1/engine/async_llm.py", line 657, in output_handler (APIServer pid=1) ERROR 04-14 02:42:14 [async_llm.py:701] outputs = await engine_core.get_output_async() (APIServer pid=1) ERROR 04-14 02:42:14 [async_llm.py:701] ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ (APIServer pid=1) ERROR 04-14 02:42:14 [async_llm.py:701] File "/usr/local/lib/python3.12/dist-packages/vllm/v1/engine/core_client.py", line 998, in get_output_async (APIServer pid=1) ERROR 04-14 02:42:14 [async_llm.py:701] raise self._format_exception(outputs) from None (APIServer pid=1) ERROR 04-14 02:42:14 [async_llm.py:701] vllm.v1.engine.exceptions.EngineDeadError: EngineCore encountered an issue. See stack trace (above) for the root cause. (APIServer pid=1) ERROR 04-14 02:42:14 [serving.py:1262] Error in chat completion stream generator. (APIServer pid=1) ERROR 04-14 02:42:14 [serving.py:1262] Traceback (most recent call last): (APIServer pid=1) ERROR 04-14 02:42:14 [serving.py:1262] File "/usr/local/lib/python3.12/dist-packages/vllm/entrypoints/openai/chat_completion/serving.py", line 586, in chat_completion_stream_generator (APIServer pid=1) ERROR 04-14 02:42:14 [serving.py:1262] async for res in result_generator: (APIServer pid=1) ERROR 04-14 02:42:14 [serving.py:1262] File "/usr/local/lib/python3.12/dist-packages/vllm/v1/engine/async_llm.py", line 576, in generate (APIServer pid=1) ERROR 04-14 02:42:14 [serving.py:1262] out = q.get_nowait() or await q.get() (APIServer pid=1) ERROR 04-14 02:42:14 [serving.py:1262] ^^^^^^^^^^^^^ (APIServer pid=1) ERROR 04-14 02:42:14 [serving.py:1262] File "/usr/local/lib/python3.12/dist-packages/vllm/v1/engine/output_processor.py", line 85, in get (APIServer pid=1) ERROR 04-14 02:42:14 [serving.py:1262] raise output (APIServer pid=1) ERROR 04-14 02:42:14 [serving.py:1262] File "/usr/local/lib/python3.12/dist-packages/vllm/v1/engine/async_llm.py", line 657, in output_handler (APIServer pid=1) ERROR 04-14 02:42:14 [serving.py:1262] outputs = await engine_core.get_output_async() (APIServer pid=1) ERROR 04-14 02:42:14 [serving.py:1262] ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ (APIServer pid=1) ERROR 04-14 02:42:14 [serving.py:1262] File "/usr/local/lib/python3.12/dist-packages/vllm/v1/engine/core_client.py", line 998, in get_output_async (APIServer pid=1) ERROR 04-14 02:42:14 [serving.py:1262] raise self._format_exception(outputs) from None (APIServer pid=1) ERROR 04-14 02:42:14 [serving.py:1262] vllm.v1.engine.exceptions.EngineDeadError: EngineCore encountered an issue. See stack trace (above) for the root cause. [rank0]:[W414 02:42:14.851794153 ProcessGroupNCCL.cpp:1575] Warning: WARNING: destroy_process_group() was not called before program exit, which can leak resources. For more info, please see https://pytorch.org/docs/stable/distributed.html#shutdown (function operator()) (APIServer pid=1) INFO 04-14 02:42:18 [loggers.py:259] Engine 000: Avg prompt throughput: 0.0 tokens/s, Avg generation throughput: 21.4 tokens/s, Running: 1 reqs, Waiting: 0 reqs, GPU KV cache usage: 0.2%, Prefix cache hit rate: 0.0% (APIServer pid=1) INFO: Shutting down (APIServer pid=1) INFO: Waiting for application shutdown. (APIServer pid=1) INFO: Application shutdown complete. (APIServer pid=1) INFO: Finished server process [1]

Fix Action

Fix / Workaround

Workaround: Appending --enforce-eager to the docker run command bypasses the crash entirely, which further confirms it is a compilation issue rather than a hardware limitation.

RAW_BUFFERClick to expand / collapse

Your current environment

<details> <summary>The output of <code>python collect_env.py</code></summary>
# I couldn't run collect_env.py easily due to the crash, but here is my exact environment based on nvidia-smi and the docker image logs:
- OS: Linux (aarch64)
- GPU: NVIDIA GB10 (Grace Blackwell)
- CUDA Version: 13.0
- Driver Version: 580.126.09
- vLLM Version: v0.19.1rc1.dev203+g0f3ce4c74
- Docker Image: vllm/vllm-openai:cu130-nightly-aarch64
</details>


### 🐛 Describe the bug

🐛 Describe the bug
When running an NVFP4 quantized MoE model (qwen3.5-35b-a3b-nvfp4) on an ARM64 server equipped with an NVIDIA GB10 (Grace Blackwell) GPU (which natively supports NVFP4), the vLLM V1 engine crashes with a torch.AcceleratorError: CUDA error: an illegal instruction was encountered.

The prefill phase successfully processes tokens (in my case, processing 57,260 prompt tokens with an 84% prefix cache hit rate), but the engine crashes specifically during the decode phase (around output token 45) inside GPUModelRunner.get_output().

Since the Blackwell hardware natively supports NVFP4 instructions, this strongly suggests a JIT compilation bug (torch.compile / Inductor) or CUDA graph issue generating invalid PTX/SASS instructions for aarch64 under the V1 Engine.

Workaround:
Appending --enforce-eager to the docker run command bypasses the crash entirely, which further confirms it is a compilation issue rather than a hardware limitation.

To Reproduce
Run the following command on a GB10 (aarch64) node:

Bash
docker run --runtime nvidia --gpus all \
    -v /home/admin/models:/workspace/models \
    -p 8081:8000 \
    --ipc=host \
    vllm/vllm-openai:cu130-nightly-aarch64 \
    --model /workspace/models/qwen3.5-35b-a3b-nvfp4 \
    --served-model-name qwen3.5-35b \
    --tensor-parallel-size 1 \
    --max-model-len 131072 \
    --enable-chunked-prefill \
    --enable-prefix-caching \
    --max-num-batched-tokens 16384 \
    --gpu-memory-utilization 0.9 \
    --reasoning-parser qwen3 \
    --tool-call-parser qwen3_xml \
    --enable-auto-tool-choice \
    --language-model-only

Relevant log output

(APIServer pid=1) INFO 04-14 02:41:48 [loggers.py:259] Engine 000: Avg prompt throughput: 1.4 tokens/s, Avg generation throughput: 9.3 tokens/s, Running: 1 reqs, Waiting: 0 reqs, GPU KV cache usage: 0.1%, Prefix cache hit rate: 0.0%
(APIServer pid=1) INFO 04-14 02:41:58 [loggers.py:259] Engine 000: Avg prompt throughput: 0.0 tokens/s, Avg generation throughput: 36.6 tokens/s, Running: 1 reqs, Waiting: 0 reqs, GPU KV cache usage: 0.1%, Prefix cache hit rate: 0.0%
(APIServer pid=1) INFO 04-14 02:42:08 [loggers.py:259] Engine 000: Avg prompt throughput: 0.0 tokens/s, Avg generation throughput: 37.0 tokens/s, Running: 1 reqs, Waiting: 0 reqs, GPU KV cache usage: 0.1%, Prefix cache hit rate: 0.0%
(EngineCore pid=166) ERROR 04-14 02:42:14 [dump_input.py:72] Dumping input data for V1 LLM engine (v0.19.1rc1.dev203+g0f3ce4c74) with config: model='/workspace/models/qwen3.5-35b-a3b-nvfp4', speculative_config=None, tokenizer='/workspace/models/qwen3.5-35b-a3b-nvfp4', skip_tokenizer_init=False, tokenizer_mode=auto, revision=None, tokenizer_revision=None, trust_remote_code=False, dtype=torch.bfloat16, max_seq_len=131072, download_dir=None, load_format=auto, tensor_parallel_size=1, pipeline_parallel_size=1, data_parallel_size=1, decode_context_parallel_size=1, dcp_comm_backend=ag_rs, disable_custom_all_reduce=False, quantization=compressed-tensors, quantization_config=None, enforce_eager=False, enable_return_routed_experts=False, kv_cache_dtype=auto, device_config=cuda, structured_outputs_config=StructuredOutputsConfig(backend='auto', disable_any_whitespace=False, disable_additional_properties=False, reasoning_parser='qwen3', reasoning_parser_plugin='', enable_in_reasoning=False), observability_config=ObservabilityConfig(show_hidden_metrics_for_version=None, otlp_traces_endpoint=None, collect_detailed_traces=None, kv_cache_metrics=False, kv_cache_metrics_sample=0.01, cudagraph_metrics=False, enable_layerwise_nvtx_tracing=False, enable_mfu_metrics=False, enable_mm_processor_stats=False, enable_logging_iteration_details=False), seed=0, served_model_name=qwen3.5-35b, enable_prefix_caching=True, enable_chunked_prefill=True, pooler_config=None, compilation_config={'mode': <CompilationMode.VLLM_COMPILE: 3>, 'debug_dump_path': None, 'cache_dir': '/root/.cache/vllm/torch_compile_cache/617ec03b22', 'compile_cache_save_format': 'binary', 'backend': 'inductor', 'custom_ops': ['none'], 'ir_enable_torch_wrap': True, 'splitting_ops': ['vllm::unified_attention_with_output', 'vllm::unified_mla_attention_with_output', 'vllm::mamba_mixer2', 'vllm::mamba_mixer', 'vllm::short_conv', 'vllm::linear_attention', 'vllm::plamo2_mamba_mixer', 'vllm::gdn_attention_core', 'vllm::olmo_hybrid_gdn_full_forward', 'vllm::kda_attention', 'vllm::sparse_attn_indexer', 'vllm::rocm_aiter_sparse_attn_indexer', 'vllm::unified_kv_cache_update', 'vllm::unified_mla_kv_cache_update'], 'compile_mm_encoder': False, 'cudagraph_mm_encoder': False, 'encoder_cudagraph_token_budgets': [], 'encoder_cudagraph_max_images_per_batch': 0, 'compile_sizes': [], 'compile_ranges_endpoints': [8192], 'inductor_compile_config': {'enable_auto_functionalized_v2': False, 'size_asserts': False, 'alignment_asserts': False, 'scalar_asserts': False, 'combo_kernels': True, 'benchmark_combo_kernel': True}, 'inductor_passes': {}, 'cudagraph_mode': <CUDAGraphMode.FULL_AND_PIECEWISE: (2, 1)>, 'cudagraph_num_of_warmups': 1, 'cudagraph_capture_sizes': [1, 2, 4, 8, 16, 24, 32, 40, 48, 56, 64, 72, 80, 88, 96, 104, 112, 120, 128, 136, 144, 152, 160, 168, 176, 184, 192, 200, 208, 216, 224, 232, 240, 248, 256, 272, 288, 304, 320, 336, 352, 368, 384, 400, 416, 432, 448, 464, 480, 496, 512], 'cudagraph_copy_inputs': False, 'cudagraph_specialize_lora': True, 'use_inductor_graph_partition': False, 'pass_config': {'fuse_norm_quant': False, 'fuse_act_quant': True, 'fuse_attn_quant': False, 'enable_sp': False, 'fuse_gemm_comms': False, 'fuse_allreduce_rms': False}, 'max_cudagraph_capture_size': 512, 'dynamic_shapes_config': {'type': <DynamicShapesType.BACKED: 'backed'>, 'evaluate_guards': False, 'assume_32_bit_indexing': False}, 'local_cache_dir': '/root/.cache/vllm/torch_compile_cache/617ec03b22/rank_0_0/backbone', 'fast_moe_cold_start': False, 'static_all_moe_layers': ['language_model.model.layers.0.mlp.experts', 'language_model.model.layers.1.mlp.experts', 'language_model.model.layers.2.mlp.experts', 'language_model.model.layers.3.mlp.experts', 'language_model.model.layers.4.mlp.experts', 'language_model.model.layers.5.mlp.experts', 'language_model.model.layers.6.mlp.experts', 'language_model.model.layers.7.mlp.experts', 'language_model.model.layers.8.mlp.experts', 'language_model.model.layers.9.mlp.experts', 'language_model.model.layers.10.mlp.experts', 'language_model.model.layers.11.mlp.experts', 'language_model.model.layers.12.mlp.experts', 'language_model.model.layers.13.mlp.experts', 'language_model.model.layers.14.mlp.experts', 'language_model.model.layers.15.mlp.experts', 'language_model.model.layers.16.mlp.experts', 'language_model.model.layers.17.mlp.experts', 'language_model.model.layers.18.mlp.experts', 'language_model.model.layers.19.mlp.experts', 'language_model.model.layers.20.mlp.experts', 'language_model.model.layers.21.mlp.experts', 'language_model.model.layers.22.mlp.experts', 'language_model.model.layers.23.mlp.experts', 'language_model.model.layers.24.mlp.experts', 'language_model.model.layers.25.mlp.experts', 'language_model.model.layers.26.mlp.experts', 'language_model.model.layers.27.mlp.experts', 'language_model.model.layers.28.mlp.experts', 'language_model.model.layers.29.mlp.experts', 'language_model.model.layers.30.mlp.experts', 'language_model.model.layers.31.mlp.experts', 'language_model.model.layers.32.mlp.experts', 'language_model.model.layers.33.mlp.experts', 'language_model.model.layers.34.mlp.experts', 'language_model.model.layers.35.mlp.experts', 'language_model.model.layers.36.mlp.experts', 'language_model.model.layers.37.mlp.experts', 'language_model.model.layers.38.mlp.experts', 'language_model.model.layers.39.mlp.experts']}, kernel_config=KernelConfig(ir_op_priority=IrOpPriorityConfig(rms_norm=['native']), enable_flashinfer_autotune=True, moe_backend='auto'),
(EngineCore pid=166) ERROR 04-14 02:42:14 [dump_input.py:79] Dumping scheduler output for model execution: SchedulerOutput(scheduled_new_reqs=[], scheduled_cached_reqs=CachedRequestData(req_ids=['chatcmpl-bcfbde213cb28031-bc849a28'],resumed_req_ids=set(),new_token_ids_lens=[],all_token_ids_lens={},new_block_ids=[([5], [6], [7], [8])],num_computed_tokens=[1056],num_output_tokens=[1043]), num_scheduled_tokens={chatcmpl-bcfbde213cb28031-bc849a28: 1}, total_num_scheduled_tokens=1, scheduled_spec_decode_tokens={}, scheduled_encoder_inputs={}, num_common_prefix_blocks=[0, 0, 0, 2], finished_req_ids=[], free_encoder_mm_hashes=[], preempted_req_ids=[], has_structured_output_requests=false, pending_structured_output_tokens=false, num_invalid_spec_tokens=null, kv_connector_metadata=null, ec_connector_metadata=null, new_block_ids_to_zero=[8])
(EngineCore pid=166) ERROR 04-14 02:42:14 [dump_input.py:81] Dumping scheduler stats: SchedulerStats(num_running_reqs=1, num_waiting_reqs=0, step_counter=0, current_wave=0, kv_cache_usage=0.0011814744801512678, encoder_cache_usage=0.0, prefix_cache_stats=PrefixCacheStats(reset=False, requests=0, queries=0, hits=0, preempted_requests=0, preempted_queries=0, preempted_hits=0), connector_prefix_cache_stats=None, kv_cache_eviction_events=[], spec_decoding_stats=None, kv_connector_stats=None, waiting_lora_adapters={}, running_lora_adapters={}, cudagraph_stats=None, perf_stats=None)
(EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112] EngineCore encountered a fatal error.
(EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112] Traceback (most recent call last):
(EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112]   File "/usr/local/lib/python3.12/dist-packages/vllm/v1/engine/core.py", line 1103, in run_engine_core
(EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112]     engine_core.run_busy_loop()
(EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112]   File "/usr/local/lib/python3.12/dist-packages/vllm/v1/engine/core.py", line 1144, in run_busy_loop
(EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112]     self._process_engine_step()
(EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112]   File "/usr/local/lib/python3.12/dist-packages/vllm/v1/engine/core.py", line 1183, in _process_engine_step
(EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112]     outputs, model_executed = self.step_fn()
(EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112]                               ^^^^^^^^^^^^^^
(EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112]   File "/usr/local/lib/python3.12/dist-packages/vllm/v1/engine/core.py", line 501, in step_with_batch_queue
(EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112]     model_output = future.result()
(EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112]                    ^^^^^^^^^^^^^^^
(EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112]   File "/usr/lib/python3.12/concurrent/futures/_base.py", line 456, in result
(EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112]     return self.__get_result()
(EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112]            ^^^^^^^^^^^^^^^^^^^
(EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112]   File "/usr/lib/python3.12/concurrent/futures/_base.py", line 401, in __get_result
(EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112]     raise self._exception
(EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112]   File "/usr/lib/python3.12/concurrent/futures/thread.py", line 59, in run
(EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112]     result = self.fn(*self.args, **self.kwargs)
(EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112]              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
(EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112]   File "/usr/local/lib/python3.12/dist-packages/vllm/v1/worker/gpu_model_runner.py", line 266, in get_output
(EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112]     self.async_copy_ready_event.synchronize()
(EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112] torch.AcceleratorError: CUDA error: an illegal instruction was encountered
(EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112] Search for `cudaErrorIllegalInstruction' in https://docs.nvidia.com/cuda/cuda-runtime-api/group__CUDART__TYPES.html for more information.
(EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112] CUDA kernel errors might be asynchronously reported at some other API call, so the stacktrace below might be incorrect.
(EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112] For debugging consider passing CUDA_LAUNCH_BLOCKING=1
(EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112] Compile with `TORCH_USE_CUDA_DSA` to enable device-side assertions.
(EngineCore pid=166) ERROR 04-14 02:42:14 [core.py:1112]
(EngineCore pid=166) Process EngineCore:
(EngineCore pid=166) Traceback (most recent call last):
(EngineCore pid=166)   File "/usr/lib/python3.12/multiprocessing/process.py", line 314, in _bootstrap
(EngineCore pid=166)     self.run()
(EngineCore pid=166)   File "/usr/lib/python3.12/multiprocessing/process.py", line 108, in run
(EngineCore pid=166)     self._target(*self._args, **self._kwargs)
(EngineCore pid=166)   File "/usr/local/lib/python3.12/dist-packages/vllm/v1/engine/core.py", line 1114, in run_engine_core
(EngineCore pid=166)     raise e
(EngineCore pid=166)   File "/usr/local/lib/python3.12/dist-packages/vllm/v1/engine/core.py", line 1103, in run_engine_core
(EngineCore pid=166)     engine_core.run_busy_loop()
(EngineCore pid=166)   File "/usr/local/lib/python3.12/dist-packages/vllm/v1/engine/core.py", line 1144, in run_busy_loop
(EngineCore pid=166)     self._process_engine_step()
(EngineCore pid=166)   File "/usr/local/lib/python3.12/dist-packages/vllm/v1/engine/core.py", line 1183, in _process_engine_step
(EngineCore pid=166)     outputs, model_executed = self.step_fn()
(EngineCore pid=166)                               ^^^^^^^^^^^^^^
(EngineCore pid=166)   File "/usr/local/lib/python3.12/dist-packages/vllm/v1/engine/core.py", line 501, in step_with_batch_queue
(EngineCore pid=166)     model_output = future.result()
(EngineCore pid=166)                    ^^^^^^^^^^^^^^^
(EngineCore pid=166)   File "/usr/lib/python3.12/concurrent/futures/_base.py", line 456, in result
(EngineCore pid=166)     return self.__get_result()
(EngineCore pid=166)            ^^^^^^^^^^^^^^^^^^^
(EngineCore pid=166)   File "/usr/lib/python3.12/concurrent/futures/_base.py", line 401, in __get_result
(EngineCore pid=166)     raise self._exception
(EngineCore pid=166)   File "/usr/lib/python3.12/concurrent/futures/thread.py", line 59, in run
(EngineCore pid=166)     result = self.fn(*self.args, **self.kwargs)
(EngineCore pid=166)              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
(EngineCore pid=166)   File "/usr/local/lib/python3.12/dist-packages/vllm/v1/worker/gpu_model_runner.py", line 266, in get_output
(EngineCore pid=166)     self.async_copy_ready_event.synchronize()
(EngineCore pid=166) torch.AcceleratorError: CUDA error: an illegal instruction was encountered
(EngineCore pid=166) Search for `cudaErrorIllegalInstruction' in https://docs.nvidia.com/cuda/cuda-runtime-api/group__CUDART__TYPES.html for more information.
(EngineCore pid=166) CUDA kernel errors might be asynchronously reported at some other API call, so the stacktrace below might be incorrect.
(EngineCore pid=166) For debugging consider passing CUDA_LAUNCH_BLOCKING=1
(EngineCore pid=166) Compile with `TORCH_USE_CUDA_DSA` to enable device-side assertions.
(EngineCore pid=166)
(APIServer pid=1) ERROR 04-14 02:42:14 [async_llm.py:701] AsyncLLM output_handler failed.
(APIServer pid=1) ERROR 04-14 02:42:14 [async_llm.py:701] Traceback (most recent call last):
(APIServer pid=1) ERROR 04-14 02:42:14 [async_llm.py:701]   File "/usr/local/lib/python3.12/dist-packages/vllm/v1/engine/async_llm.py", line 657, in output_handler
(APIServer pid=1) ERROR 04-14 02:42:14 [async_llm.py:701]     outputs = await engine_core.get_output_async()
(APIServer pid=1) ERROR 04-14 02:42:14 [async_llm.py:701]               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
(APIServer pid=1) ERROR 04-14 02:42:14 [async_llm.py:701]   File "/usr/local/lib/python3.12/dist-packages/vllm/v1/engine/core_client.py", line 998, in get_output_async
(APIServer pid=1) ERROR 04-14 02:42:14 [async_llm.py:701]     raise self._format_exception(outputs) from None
(APIServer pid=1) ERROR 04-14 02:42:14 [async_llm.py:701] vllm.v1.engine.exceptions.EngineDeadError: EngineCore encountered an issue. See stack trace (above) for the root cause.
(APIServer pid=1) ERROR 04-14 02:42:14 [serving.py:1262] Error in chat completion stream generator.
(APIServer pid=1) ERROR 04-14 02:42:14 [serving.py:1262] Traceback (most recent call last):
(APIServer pid=1) ERROR 04-14 02:42:14 [serving.py:1262]   File "/usr/local/lib/python3.12/dist-packages/vllm/entrypoints/openai/chat_completion/serving.py", line 586, in chat_completion_stream_generator
(APIServer pid=1) ERROR 04-14 02:42:14 [serving.py:1262]     async for res in result_generator:
(APIServer pid=1) ERROR 04-14 02:42:14 [serving.py:1262]   File "/usr/local/lib/python3.12/dist-packages/vllm/v1/engine/async_llm.py", line 576, in generate
(APIServer pid=1) ERROR 04-14 02:42:14 [serving.py:1262]     out = q.get_nowait() or await q.get()
(APIServer pid=1) ERROR 04-14 02:42:14 [serving.py:1262]                             ^^^^^^^^^^^^^
(APIServer pid=1) ERROR 04-14 02:42:14 [serving.py:1262]   File "/usr/local/lib/python3.12/dist-packages/vllm/v1/engine/output_processor.py", line 85, in get
(APIServer pid=1) ERROR 04-14 02:42:14 [serving.py:1262]     raise output
(APIServer pid=1) ERROR 04-14 02:42:14 [serving.py:1262]   File "/usr/local/lib/python3.12/dist-packages/vllm/v1/engine/async_llm.py", line 657, in output_handler
(APIServer pid=1) ERROR 04-14 02:42:14 [serving.py:1262]     outputs = await engine_core.get_output_async()
(APIServer pid=1) ERROR 04-14 02:42:14 [serving.py:1262]               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
(APIServer pid=1) ERROR 04-14 02:42:14 [serving.py:1262]   File "/usr/local/lib/python3.12/dist-packages/vllm/v1/engine/core_client.py", line 998, in get_output_async
(APIServer pid=1) ERROR 04-14 02:42:14 [serving.py:1262]     raise self._format_exception(outputs) from None
(APIServer pid=1) ERROR 04-14 02:42:14 [serving.py:1262] vllm.v1.engine.exceptions.EngineDeadError: EngineCore encountered an issue. See stack trace (above) for the root cause.
[rank0]:[W414 02:42:14.851794153 ProcessGroupNCCL.cpp:1575] Warning: WARNING: destroy_process_group() was not called before program exit, which can leak resources. For more info, please see https://pytorch.org/docs/stable/distributed.html#shutdown (function operator())
(APIServer pid=1) INFO 04-14 02:42:18 [loggers.py:259] Engine 000: Avg prompt throughput: 0.0 tokens/s, Avg generation throughput: 21.4 tokens/s, Running: 1 reqs, Waiting: 0 reqs, GPU KV cache usage: 0.2%, Prefix cache hit rate: 0.0%
(APIServer pid=1) INFO:     Shutting down
(APIServer pid=1) INFO:     Waiting for application shutdown.
(APIServer pid=1) INFO:     Application shutdown complete.
(APIServer pid=1) INFO:     Finished server process [1]


### Before submitting a new issue...

- [x] Make sure you already searched for relevant issues, and asked the chatbot living at the bottom right corner of the [documentation page](https://docs.vllm.ai/en/latest/), which can answer lots of frequently asked questions.

extent analysis

TL;DR

The most likely fix is to append the --enforce-eager flag to the docker run command to bypass the compilation issue.

Guidance

  • The error message torch.AcceleratorError: CUDA error: an illegal instruction was encountered suggests a compilation issue with the CUDA kernel.
  • The fact that appending --enforce-eager to the docker run command bypasses the crash confirms that it is a compilation issue rather than a hardware limitation.
  • To further debug the issue, consider passing CUDA_LAUNCH_BLOCKING=1 to enable synchronous CUDA kernel launches, which can help identify the exact kernel causing the error.
  • Compile with TORCH_USE_CUDA_DSA to enable device-side assertions, which can provide more detailed error messages.

Example

No code snippet is provided as the issue is related to a specific hardware and software configuration.

Notes

The issue is specific to the NVIDIA GB10 (Grace Blackwell) GPU and the vLLM V1 engine, and may not be reproducible on other hardware or software configurations.

Recommendation

Apply the workaround by appending --enforce-eager to the docker run command, as it has been confirmed to bypass the crash. This will allow the model to run, but may not provide the optimal performance. Further debugging and investigation are needed to resolve the underlying compilation issue.

Vote matrix · Quick signals

Works
Did the solution work? Tap to confirm.
Easy Fix
Was it a quick fix?
Time Saver
Did it save you time?
Blocking
Was it severely blocking?
Common Issue
Are others likely hitting this too?
Flaky / Intermittent
Is it intermittent?
Verified / Reproducible
Can you reproduce it reliably?
Loading…

Still need to ship something?

×6

Another batch ranked right after the header list — different links, same matching logic.

Back to top recommendations

TRENDING