[Bugfix][Model] Fix Qwen3.5 MTP for text-only checkpoints - #50734
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Two gaps in the Qwen3.5 MTP speculative decoding path: - `SpeculativeConfig.hf_config_override` only matched the `qwen3_5` / `qwen3_5_moe` model types. Since vllm-project#50210 registered `qwen3_5_text` and `qwen3_5_moe_text` in `_CONFIG_REGISTRY`, a text-only checkpoint that carries `mtp_num_hidden_layers` never gets rewritten to `qwen3_5_mtp`, so `--speculative-config '{"method":"mtp",...}'` fails to resolve the draft architecture. Match the text-only model types as well. - `Qwen3_5MTP` / `Qwen3_5MoeMTP` declare `SupportsMultiModal` but have no registered multi-modal processor, so `_processor_factory` is absent and `MultiModalRegistry._get_model_cls()` raises "has no registered multimodal processor". Register the same processor trio that `Qwen3_5ForConditionalGeneration` uses. Signed-off-by: efschu <51944948+efschu@users.noreply.github.com>
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August 2, 2026 08:33
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Could you show the stack trace for this? Perhaps we could solve this inside the multi-modal registry itself instead of having to edit the model definition |
…registry Drops the processor registration this PR had added to `Qwen3_5MTP` / `Qwen3_5MoeMTP` and leaves the model definition at its upstream state. Registering the Qwen3-VL processor trio on the drafters made `MultiModalRegistry.supports_multimodal_inputs()` return True for the draft `ModelConfig`, so a text-only drafter was pushed through the full multi-modal path. Without it the registry already falls back to text-only mode for a class that declares `SupportsMultiModal` but registers no processor (`vllm/multimodal/registry.py`), which is the shape the other drafters for multi-modal targets rely on as well (`Exaone4_5_MTP`, `MiMoV2OmniMTP`). The remaining change in this PR is the `hf_config_override` fix for the `qwen3_5_text` / `qwen3_5_moe_text` model types. Signed-off-by: efschu <51944948+efschu@users.noreply.github.com>
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No stack trace — I went back to check and could not reproduce one on current main, so that part of the description was wrong. The one leftover is the "treated as multimodal but has no registered multimodal processor" warning that now fires at startup for every MTP drafter; happy to silence that registry-side for |
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Let's do it in this PR as well |
…models `MultiModalRegistry.supports_multimodal_inputs()` warns when a model declares `SupportsMultiModal` but registers no multi-modal processor, then falls back to text-only mode. Speculative drafters for multimodal targets (`Qwen3_5MTP`, `Exaone4_5_MTP`, `MiMoV2OmniMTP`) are exactly that shape on purpose: they implement `embed_input_ids` so they can consume the embeddings merged by the target model, but they never run a processor of their own. Text-only mode is the expected outcome for them, so the warning is noise on every startup with such a drafter. Skip it for model configs with `runner_type == "draft"`. The return value and every other code path are unchanged. Signed-off-by: efschu <51944948+efschu@users.noreply.github.com>
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August 3, 2026 13:05
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Done in a6b160b — |
| match="friendly-model-name is not a multimodal model", | ||
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| MULTIMODAL_REGISTRY.create_processor(model_config) | ||
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Let's remove this test, the warning is basically by definition anyway
Per review: the warning is by definition tied to the branch it guards, so the test adds no signal. Signed-off-by: efschu <51944948+efschu@users.noreply.github.com>
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✅ Triggered Buildkite CI #83121 for commit |
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…ct#50734) Signed-off-by: efschu <51944948+efschu@users.noreply.github.com>
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### What this PR does / why we need it? This PR backports the Qwen3.5 text-only RoPE handling and ModelSlim packed-module mappings from [vLLM PR #50734](vllm-project/vllm#50734). Text-only Qwen3.5-family checkpoints use the model types qwen3_5_text or qwen3_5_moe_text. Unlike multimodal Qwen3.5 checkpoints, they do not expose multimodal RoPE fields such as mrope_section. Before this change, the Ascend Qwen3.5 attention patch selected the multimodal RoPE path based only on the qwen3_5 model-type prefix. This could cause text-only checkpoints to access missing multimodal RoPE attributes. ModelSlim also lacked packed-module mappings for the text-only dense and MoE model types. The change: - selects the multimodal RoPE path only when mrope_section is available; - keeps text-only Qwen3.5 checkpoints on the standard RoPE path; - adds ModelSlim packed-module mappings for qwen3_5_text; - adds ModelSlim packed-module and expert mappings for qwen3_5_moe_text; - adds focused unit coverage for RoPE selection and ModelSlim mappings. This is a scoped backport. It does not include the model registration, hybrid-cache wrappers, MTP configuration conversion, or documentation changes from the source PR. Related PR: [vllm-project/vllm#50734](vllm-project/vllm#50734) ### Does this PR introduce _any_ user-facing change? Yes. When the corresponding text-only Qwen3.5 model integration is available, checkpoints using qwen3_5_text or qwen3_5_moe_text no longer incorrectly enter the multimodal RoPE path. ModelSlim W8A8 checkpoints using these model types can also resolve the existing packed QKV, gate/up projection, GDN projection, and MoE expert mappings. ### How was this patch tested? Added unit coverage for: - standard RoPE selection for qwen3_5_moe_text; - multimodal RoPE selection when mrope_section exists; - ModelSlim packed-module mappings for qwen3_5_text; - ModelSlim expert mappings for qwen3_5_moe_text. git diff --check passed. Python syntax compilation passed for all four changed files. Targeted pytest execution was not available in the local environment because pytest is not installed. Ruff was not available in the local environment, so no Ruff result is claimed. No real Ascend NPU or checkpoint inference validation was performed for this scoped backport. vLLM version: current branch dependency vLLM main: current branch dependency - vLLM version: v0.27.1 - vLLM main: vllm-project/vllm@ba07e4a Signed-off-by: Erkong <Erkong@noreply.gitcode.com> Co-authored-by: Erkong <Erkong@noreply.gitcode.com>
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…14885) ### What this PR does / why we need it? This PR backports the Qwen3.5 text-only RoPE handling and ModelSlim packed-module mappings from [vLLM PR #50734](vllm-project/vllm#50734). Text-only Qwen3.5-family checkpoints use the model types qwen3_5_text or qwen3_5_moe_text. Unlike multimodal Qwen3.5 checkpoints, they do not expose multimodal RoPE fields such as mrope_section. Before this change, the Ascend Qwen3.5 attention patch selected the multimodal RoPE path based only on the qwen3_5 model-type prefix. This could cause text-only checkpoints to access missing multimodal RoPE attributes. ModelSlim also lacked packed-module mappings for the text-only dense and MoE model types. The change: - selects the multimodal RoPE path only when mrope_section is available; - keeps text-only Qwen3.5 checkpoints on the standard RoPE path; - adds ModelSlim packed-module mappings for qwen3_5_text; - adds ModelSlim packed-module and expert mappings for qwen3_5_moe_text; - adds focused unit coverage for RoPE selection and ModelSlim mappings. This is a scoped backport. It does not include the model registration, hybrid-cache wrappers, MTP configuration conversion, or documentation changes from the source PR. Related PR: [vllm-project/vllm#50734](vllm-project/vllm#50734) ### Does this PR introduce _any_ user-facing change? Yes. When the corresponding text-only Qwen3.5 model integration is available, checkpoints using qwen3_5_text or qwen3_5_moe_text no longer incorrectly enter the multimodal RoPE path. ModelSlim W8A8 checkpoints using these model types can also resolve the existing packed QKV, gate/up projection, GDN projection, and MoE expert mappings. ### How was this patch tested? Added unit coverage for: - standard RoPE selection for qwen3_5_moe_text; - multimodal RoPE selection when mrope_section exists; - ModelSlim packed-module mappings for qwen3_5_text; - ModelSlim expert mappings for qwen3_5_moe_text. git diff --check passed. Python syntax compilation passed for all four changed files. Targeted pytest execution was not available in the local environment because pytest is not installed. Ruff was not available in the local environment, so no Ruff result is claimed. No real Ascend NPU or checkpoint inference validation was performed for this scoped backport. vLLM version: current branch dependency vLLM main: current branch dependency - vLLM version: v0.27.1 - vLLM main: vllm-project/vllm@ba07e4a Signed-off-by: Erkong <Erkong@noreply.gitcode.com> Co-authored-by: Erkong <Erkong@noreply.gitcode.com> Signed-off-by: QiuChunshuo <qiuchunshuo@huawei.com>
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…14885) ### What this PR does / why we need it? This PR backports the Qwen3.5 text-only RoPE handling and ModelSlim packed-module mappings from [vLLM PR #50734](vllm-project/vllm#50734). Text-only Qwen3.5-family checkpoints use the model types qwen3_5_text or qwen3_5_moe_text. Unlike multimodal Qwen3.5 checkpoints, they do not expose multimodal RoPE fields such as mrope_section. Before this change, the Ascend Qwen3.5 attention patch selected the multimodal RoPE path based only on the qwen3_5 model-type prefix. This could cause text-only checkpoints to access missing multimodal RoPE attributes. ModelSlim also lacked packed-module mappings for the text-only dense and MoE model types. The change: - selects the multimodal RoPE path only when mrope_section is available; - keeps text-only Qwen3.5 checkpoints on the standard RoPE path; - adds ModelSlim packed-module mappings for qwen3_5_text; - adds ModelSlim packed-module and expert mappings for qwen3_5_moe_text; - adds focused unit coverage for RoPE selection and ModelSlim mappings. This is a scoped backport. It does not include the model registration, hybrid-cache wrappers, MTP configuration conversion, or documentation changes from the source PR. Related PR: [vllm-project/vllm#50734](vllm-project/vllm#50734) ### Does this PR introduce _any_ user-facing change? Yes. When the corresponding text-only Qwen3.5 model integration is available, checkpoints using qwen3_5_text or qwen3_5_moe_text no longer incorrectly enter the multimodal RoPE path. ModelSlim W8A8 checkpoints using these model types can also resolve the existing packed QKV, gate/up projection, GDN projection, and MoE expert mappings. ### How was this patch tested? Added unit coverage for: - standard RoPE selection for qwen3_5_moe_text; - multimodal RoPE selection when mrope_section exists; - ModelSlim packed-module mappings for qwen3_5_text; - ModelSlim expert mappings for qwen3_5_moe_text. git diff --check passed. Python syntax compilation passed for all four changed files. Targeted pytest execution was not available in the local environment because pytest is not installed. Ruff was not available in the local environment, so no Ruff result is claimed. No real Ascend NPU or checkpoint inference validation was performed for this scoped backport. vLLM version: current branch dependency vLLM main: current branch dependency - vLLM version: v0.27.1 - vLLM main: vllm-project/vllm@ba07e4a Signed-off-by: Erkong <Erkong@noreply.gitcode.com> Co-authored-by: Erkong <Erkong@noreply.gitcode.com>
Lethobenthos20
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Sep 4, 2026
…14885) ### What this PR does / why we need it? This PR backports the Qwen3.5 text-only RoPE handling and ModelSlim packed-module mappings from [vLLM PR #50734](vllm-project/vllm#50734). Text-only Qwen3.5-family checkpoints use the model types qwen3_5_text or qwen3_5_moe_text. Unlike multimodal Qwen3.5 checkpoints, they do not expose multimodal RoPE fields such as mrope_section. Before this change, the Ascend Qwen3.5 attention patch selected the multimodal RoPE path based only on the qwen3_5 model-type prefix. This could cause text-only checkpoints to access missing multimodal RoPE attributes. ModelSlim also lacked packed-module mappings for the text-only dense and MoE model types. The change: - selects the multimodal RoPE path only when mrope_section is available; - keeps text-only Qwen3.5 checkpoints on the standard RoPE path; - adds ModelSlim packed-module mappings for qwen3_5_text; - adds ModelSlim packed-module and expert mappings for qwen3_5_moe_text; - adds focused unit coverage for RoPE selection and ModelSlim mappings. This is a scoped backport. It does not include the model registration, hybrid-cache wrappers, MTP configuration conversion, or documentation changes from the source PR. Related PR: [vllm-project/vllm#50734](vllm-project/vllm#50734) ### Does this PR introduce _any_ user-facing change? Yes. When the corresponding text-only Qwen3.5 model integration is available, checkpoints using qwen3_5_text or qwen3_5_moe_text no longer incorrectly enter the multimodal RoPE path. ModelSlim W8A8 checkpoints using these model types can also resolve the existing packed QKV, gate/up projection, GDN projection, and MoE expert mappings. ### How was this patch tested? Added unit coverage for: - standard RoPE selection for qwen3_5_moe_text; - multimodal RoPE selection when mrope_section exists; - ModelSlim packed-module mappings for qwen3_5_text; - ModelSlim expert mappings for qwen3_5_moe_text. git diff --check passed. Python syntax compilation passed for all four changed files. Targeted pytest execution was not available in the local environment because pytest is not installed. Ruff was not available in the local environment, so no Ruff result is claimed. No real Ascend NPU or checkpoint inference validation was performed for this scoped backport. vLLM version: current branch dependency vLLM main: current branch dependency - vLLM version: v0.27.1 - vLLM main: vllm-project/vllm@ba07e4a Signed-off-by: Erkong <Erkong@noreply.gitcode.com> Co-authored-by: Erkong <Erkong@noreply.gitcode.com>
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What
Two gaps that keep
--speculative-config '{"method":"mtp",...}'from working on Qwen3.5 checkpoints that ship only the text config.Details
1. The MTP config override does not know the text-only model types.
SpeculativeConfig.hf_config_overridematches onlyqwen3_5/qwen3_5_moe(vllm/config/speculative.py). #50210 registeredqwen3_5_textandqwen3_5_moe_textin_CONFIG_REGISTRY(vllm/transformers_utils/config.py) and addedQwen3_5ForCausalLM/Qwen3_5MoeForCausalLMto the model registry, so such a checkpoint now loads for plain generation — but itsmtp_num_hidden_layersis never rewritten into aqwen3_5_mtpdraft config, so MTP fails to resolve a draft architecture. Extended the match; the MoE branch keys off both MoE spellings.2. The MTP classes declare multimodal support but register no processor.
Qwen3_5MTPandQwen3_5MoeMTPinheritSupportsMultiModal, soModelRegistry.is_multimodal_modelreports them as multimodal, but neither carries a_processor_factory.MultiModalRegistry._get_model_cls()then raisesModel class Qwen3_5MTP has no registered multimodal processor(vllm/multimodal/registry.py). Observed on currentmain:Registered the same
Qwen3VLMultiModalProcessor/Qwen3_5ProcessingInfo/Qwen3VLDummyInputsBuildertrio thatQwen3_5ForConditionalGenerationalready uses.Verification
pytest tests/models/test_qwen3_5_mtp_config.py— 6 passed on this branch. With the two source files reverted tomain, 4 of the 6 fail (2 per item above), so the tests do exercise the change. CPU only, no checkpoint download.ruff check/ruff format --checkand the repo'scheck_spdx_header,check_init_lazy_imports,check_forbidden_imports,check_torch_cuda,check_boolean_context_manager,validate_confighooks.Limits
Config and registration only; no model code changes. End-to-end MTP decoding against a text-only Qwen3.5 checkpoint was exercised earlier on my own hardware and is not re-run here.