[Model] Migrate MistralLarge3ForCausalLM to AutoWeightsLoader (#48153)

Signed-off-by: Yuchen Fan <functionhx@gmail.com>

FAN YUCHEN committed Jul 10, 2026 at 20:27 UTC fabec87f63cdf0725d48e3eb6fdef9799837bcaf
2 files changed +89 -57
vllm/model_executor/models/mistral_large_3.py
+80 -51
@@ -2,62 +2,91 @@
2 # SPDX-FileCopyrightText: Copyright contributors to the vLLM project
3 from collections.abc import Iterable
4
5 -import regex as re
5 +import regex
6 import torch
7
8 from vllm.model_executor.models.deepseek_v2 import DeepseekV3ForCausalLM
9 +from vllm.model_executor.models.utils import AutoWeightsLoader, WeightsMapper
10
11
12 class MistralLarge3ForCausalLM(DeepseekV3ForCausalLM):
12 - # fmt: off
13 - remapping = {
14 - r"layers\.(\d+)\.attention_norm\.weight": r"model.layers.\1.input_layernorm.weight", # noqa: E501
15 - r"layers\.(\d+)\.attention\.wq_a\.(\w+)": r"model.layers.\1.self_attn.q_a_proj.\2", # noqa: E501
16 - r"layers\.(\d+)\.attention\.q_a_norm\.weight": r"model.layers.\1.self_attn.q_a_layernorm.weight", # noqa: E501
17 - r"layers\.(\d+)\.attention\.wq_b\.(\w+)": r"model.layers.\1.self_attn.q_b_proj.\2", # noqa: E501
18 - r"layers\.(\d+)\.attention\.wkv_a_with_mqa\.(\w+)": r"model.layers.\1.self_attn.kv_a_proj_with_mqa.\2", # noqa: E501
19 - r"layers\.(\d+)\.attention\.kv_a_norm\.weight": r"model.layers.\1.self_attn.kv_a_layernorm.weight", # noqa: E501
20 - r"layers\.(\d+)\.attention\.wkv_b\.(\w+)": r"model.layers.\1.self_attn.kv_b_proj.\2", # noqa: E501
21 - r"layers\.(\d+)\.attention\.wo\.(\w+)": r"model.layers.\1.self_attn.o_proj.\2", # noqa: E501
22 - r"layers\.(\d+)\.ffn_norm\.weight": r"model.layers.\1.post_attention_layernorm.weight", # noqa: E501
23 - r"layers\.(\d+)\.feed_forward\.w1\.(\w+)": r"model.layers.\1.mlp.gate_proj.\2", # noqa: E501
24 - r"layers\.(\d+)\.feed_forward\.w2\.(\w+)": r"model.layers.\1.mlp.down_proj.\2", # noqa: E501
25 - r"layers\.(\d+)\.feed_forward\.w3\.(\w+)": r"model.layers.\1.mlp.up_proj.\2", # noqa: E501
26 - r"layers\.(\d+)\.gate\.weight": r"model.layers.\1.mlp.gate.weight", # noqa: E501
27 - r"layers\.(\d+)\.shared_experts\.w1\.(\w+)": r"model.layers.\1.mlp.shared_experts.gate_proj.\2", # noqa: E501
28 - r"layers\.(\d+)\.shared_experts\.w2\.(\w+)": r"model.layers.\1.mlp.shared_experts.down_proj.\2", # noqa: E501
29 - r"layers\.(\d+)\.shared_experts\.w3\.(\w+)": r"model.layers.\1.mlp.shared_experts.up_proj.\2", # noqa: E501
30 - r"layers\.(\d+)\.experts\.(\d+)\.w1\.(\w+)": r"model.layers.\1.mlp.experts.\2.gate_proj.\3", # noqa: E501
31 - r"layers\.(\d+)\.experts\.(\d+)\.w2\.(\w+)": r"model.layers.\1.mlp.experts.\2.down_proj.\3", # noqa: E501
32 - r"layers\.(\d+)\.experts\.(\d+)\.w3\.(\w+)": r"model.layers.\1.mlp.experts.\2.up_proj.\3", # noqa: E501
33 - r"norm\.weight": "model.norm.weight", # noqa: E501
34 - r"tok_embeddings\.weight": "model.embed_tokens.weight", # noqa: E501
35 - r"output\.weight": "lm_head.weight", # noqa: E501
36 - }
37 - # fmt: on
13 + # WeightsMapper applies all matching patterns sequentially (no break on first
14 + # match). This is safe here because every pattern is anchored at both ends
15 + # (\A...\Z) and after substitution the resulting key always starts with
16 + # "model." or "lm_head.", so no later pattern can accidentally match again.
17 + hf_to_vllm_mapper = WeightsMapper(
18 + orig_to_new_regex={ # noqa: B950
19 + regex.compile(
20 + r"\Alayers\.(\d+)\.attention_norm\.weight\Z"
21 + ): r"model.layers.\1.input_layernorm.weight",
22 + regex.compile(
23 + r"\Alayers\.(\d+)\.attention\.wq_a\.(\w+)\Z"
24 + ): r"model.layers.\1.self_attn.q_a_proj.\2",
25 + regex.compile(
26 + r"\Alayers\.(\d+)\.attention\.q_a_norm\.weight\Z"
27 + ): r"model.layers.\1.self_attn.q_a_layernorm.weight",
28 + regex.compile(
29 + r"\Alayers\.(\d+)\.attention\.wq_b\.(\w+)\Z"
30 + ): r"model.layers.\1.self_attn.q_b_proj.\2",
31 + regex.compile(
32 + r"\Alayers\.(\d+)\.attention\.wkv_a_with_mqa\.(\w+)\Z"
33 + ): r"model.layers.\1.self_attn.kv_a_proj_with_mqa.\2",
34 + regex.compile(
35 + r"\Alayers\.(\d+)\.attention\.kv_a_norm\.weight\Z"
36 + ): r"model.layers.\1.self_attn.kv_a_layernorm.weight",
37 + regex.compile(
38 + r"\Alayers\.(\d+)\.attention\.wkv_b\.(\w+)\Z"
39 + ): r"model.layers.\1.self_attn.kv_b_proj.\2",
40 + regex.compile(
41 + r"\Alayers\.(\d+)\.attention\.wo\.(\w+)\Z"
42 + ): r"model.layers.\1.self_attn.o_proj.\2",
43 + regex.compile(
44 + r"\Alayers\.(\d+)\.ffn_norm\.weight\Z"
45 + ): r"model.layers.\1.post_attention_layernorm.weight",
46 + regex.compile(
47 + r"\Alayers\.(\d+)\.feed_forward\.w1\.(\w+)\Z"
48 + ): r"model.layers.\1.mlp.gate_proj.\2",
49 + regex.compile(
50 + r"\Alayers\.(\d+)\.feed_forward\.w2\.(\w+)\Z"
51 + ): r"model.layers.\1.mlp.down_proj.\2",
52 + regex.compile(
53 + r"\Alayers\.(\d+)\.feed_forward\.w3\.(\w+)\Z"
54 + ): r"model.layers.\1.mlp.up_proj.\2",
55 + regex.compile(
56 + r"\Alayers\.(\d+)\.gate\.weight\Z"
57 + ): r"model.layers.\1.mlp.gate.weight",
58 + regex.compile(
59 + r"\Alayers\.(\d+)\.shared_experts\.w1\.(\w+)\Z"
60 + ): r"model.layers.\1.mlp.shared_experts.gate_proj.\2",
61 + regex.compile(
62 + r"\Alayers\.(\d+)\.shared_experts\.w2\.(\w+)\Z"
63 + ): r"model.layers.\1.mlp.shared_experts.down_proj.\2",
64 + regex.compile(
65 + r"\Alayers\.(\d+)\.shared_experts\.w3\.(\w+)\Z"
66 + ): r"model.layers.\1.mlp.shared_experts.up_proj.\2",
67 + regex.compile(
68 + r"\Alayers\.(\d+)\.experts\.(\d+)\.w1\.(\w+)\Z"
69 + ): r"model.layers.\1.mlp.experts.\2.gate_proj.\3",
70 + regex.compile(
71 + r"\Alayers\.(\d+)\.experts\.(\d+)\.w2\.(\w+)\Z"
72 + ): r"model.layers.\1.mlp.experts.\2.down_proj.\3",
73 + regex.compile(
74 + r"\Alayers\.(\d+)\.experts\.(\d+)\.w3\.(\w+)\Z"
75 + ): r"model.layers.\1.mlp.experts.\2.up_proj.\3",
76 + regex.compile(r"\Anorm\.weight\Z"): "model.norm.weight",
77 + regex.compile(r"\Atok_embeddings\.weight\Z"): "model.embed_tokens.weight",
78 + regex.compile(r"\Aoutput\.weight\Z"): "lm_head.weight",
79 + },
80 + orig_to_new_suffix={
81 + ".qscale_act": ".input_scale",
82 + ".qscale_weight": ".weight_scale",
83 + },
84 + )
85
86 + # Bypass super().load_weights() and construct AutoWeightsLoader(self)
87 + # directly (same pattern as Qwen2ForCausalLM). Any logic in the parent
88 + # class's load_weights is a thin wrapper around AutoWeightsLoader, and
89 + # we must apply hf_to_vllm_mapper before the loader walks the tree.
90 def load_weights(self, weights: Iterable[tuple[str, torch.Tensor]]) -> set[str]:
40 - return super().load_weights(map(self._remap_mistral_to_ds, weights))
41 -
42 - def _remap_mistral_to_ds(
43 - self, weight: tuple[str, torch.Tensor]
44 - ) -> tuple[str, torch.Tensor]:
45 - """Remap Mistral parameters to DeepseekV2 parameters."""
46 - name, loaded_weight = weight
47 -
48 - for k, v in self.remapping.items():
49 - match = re.fullmatch(k, name)
50 - if match:
51 - name = re.sub(k, v, name)
52 - break
53 - else:
54 - raise ValueError(f"Cannot remap {name}")
55 -
56 - # Remapping scale names. We could do this in the regex above but it
57 - # would triple the number of lines for most layers.
58 - if name.endswith(".qscale_act"):
59 - name = re.sub(r"\.qscale_act$", ".input_scale", name)
60 - elif name.endswith(".qscale_weight"):
61 - name = re.sub(r"\.qscale_weight$", ".weight_scale", name)
62 -
63 - return name, loaded_weight
91 + loader = AutoWeightsLoader(self)
92 + return loader.load_weights(weights, mapper=self.hf_to_vllm_mapper)
vllm/model_executor/models/mistral_large_3_eagle.py
+9 -6
@@ -5,6 +5,7 @@ import copy
5 from collections.abc import Iterable
6 from functools import partial
7
8 +import regex
9 import torch
10 import torch.nn as nn
11
@@ -22,7 +23,7 @@ from vllm.model_executor.models.deepseek_v2 import (
23 from vllm.model_executor.models.mistral_large_3 import MistralLarge3ForCausalLM
24
25 from .interfaces import SupportsMultiModal
25 -from .utils import make_empty_intermediate_tensors_factory, maybe_prefix
26 +from .utils import WeightsMapper, make_empty_intermediate_tensors_factory, maybe_prefix
27
28 logger = init_logger(__name__)
29
@@ -107,11 +108,13 @@ class EagleMistralLarge3Model(DeepseekV2Model):
108
109
110 class EagleMistralLarge3ForCausalLM(MistralLarge3ForCausalLM):
110 - remapping = MistralLarge3ForCausalLM.remapping | {
111 - r"eagle_linear\.weight": r"model.fc.weight",
112 - r"eagle_linear\.qscale_act": r"model.fc.input_scale",
113 - r"eagle_linear\.qscale_weight": r"model.fc.weight_scale",
114 - }
111 + hf_to_vllm_mapper = MistralLarge3ForCausalLM.hf_to_vllm_mapper | WeightsMapper(
112 + orig_to_new_regex={
113 + regex.compile(r"\Aeagle_linear\.weight\Z"): r"model.fc.weight",
114 + regex.compile(r"\Aeagle_linear\.qscale_act\Z"): r"model.fc.input_scale",
115 + regex.compile(r"\Aeagle_linear\.qscale_weight\Z"): r"model.fc.weight_scale",
116 + },
117 + )
118
119 def __init__(self, *, vllm_config: VllmConfig, prefix: str = ""):
120 target_layer_num = vllm_config.model_config.get_num_layers(