[ROCm][Quantization] GPT_OSS in amd-quark format model loading and emulations (#29008)

Signed-off-by: xuebwang-amd <xuebwang@amd.com>
Signed-off-by: Robert Shaw <robshaw@redhat.com>
Co-authored-by: Robert Shaw <robshaw@redhat.com>
Co-authored-by: Robert Shaw <114415538+robertgshaw2-redhat@users.noreply.github.com>

tests/kernels/moe/test_gpt_oss_triton_kernels.py

@@ -22,7 +22,7 @@ from triton_kernels.tensor import FP4, convert_layout, wrap_torch_tensor
 from triton_kernels.tensor_details import layout
 from triton_kernels.testing import assert_close
 
-from vllm.model_executor.layers.fused_moe.config import FusedMoEQuantConfig
+from vllm.model_executor.layers.fused_moe.config import mxfp4_w4a16_moe_quant_config
 from vllm.model_executor.layers.fused_moe.gpt_oss_triton_kernels_moe import (
     triton_kernel_moe_forward,
 )
@@ -298,12 +298,18 @@ def test_equiv(num_token, a_dtype, w_dtype, tp, workspace_init):
         pc2,
     ) = init_compute_data(M, K, N, E, a_dtype, w_dtype, num_warps=8)
 
-    quant_config = FusedMoEQuantConfig.make(
-        w1_bias=w1_bias_tri,
-        w2_bias=w2_bias_tri,
-        w1_scale=pc1,
-        w2_scale=pc2,
-    )
+    if a_dtype == "bf16" and w_dtype == "mx4":
+        quant_config = mxfp4_w4a16_moe_quant_config(
+            w1_scale=pc1,
+            w2_scale=pc2,
+            w1_bias=w1_bias_tri,
+            w2_bias=w2_bias_tri,
+        )
+    else:
+        raise NotImplementedError(
+            f"Quantization configuration for activation={a_dtype} and weight={w_dtype} "
+            f"has not been implemented."
+        )
 
     out_triton_monolithic = triton_kernel_moe_forward(
         hidden_states=x_tri,

tests/models/quantization/test_gpt_oss_attn_quantization.py → tests/models/quantization/test_gpt_oss.py

 # SPDX-License-Identifier: Apache-2.0
 # SPDX-FileCopyrightText: Copyright contributors to the vLLM project
-"""Test attention quantization of gpt-oss model.
-The qkv_proj and o_proj in self_attention can be either quantized or excluded.
+"""
+End-to-end accuracy test for GPT-OSS model quantization.
 
-Run `pytest tests/models/quantization/test_gpt_oss_attn_quantization.py`.
+Config:
+    Task:   gsm8k_platinum
+    Filter: flexible-extract
+    n-shot: 5
+    Metric: exact_match
 
+Run: pytest tests/models/quantization/test_gpt_oss.py
 """
 
 import importlib
@@ -16,11 +21,18 @@ import lm_eval
 import pytest
 from packaging import version
 
-MODEL_NAMES = ["amd/gpt-oss-20b-customized-attention-quantization"]
+MODEL_ACCURACIES = {
+    # Full quantization: attention linears and MoE linears
+    "amd/gpt-oss-20b-WFP8-AFP8-KVFP8": 0.89,
+    # MoE linears only quantization
+    "amd/gpt-oss-20b-MoE-Quant-W-MXFP4-A-FP8-KV-FP8": 0.89,
+    # MoE linears only quantization
+    # "amd/gpt-oss-20b-MoE-Quant-W-MXFP4-A-MXFP4-KV-FP8": 0.90,
+}
 
 QUARK_MXFP4_AVAILABLE = importlib.util.find_spec("quark") is not None and version.parse(
     importlib.metadata.version("amd-quark")
-) >= version.parse("0.8.99")
+) >= version.parse("0.9.0")
 
 
 def has_huggingface_access(repo):
@@ -32,7 +44,7 @@ def has_huggingface_access(repo):
 
 
 HF_HUB_AMD_ORG_ACCESS = all(
-    [has_huggingface_access(model_name) for model_name in MODEL_NAMES]
+    [has_huggingface_access(model_name) for model_name in MODEL_ACCURACIES]
 )
 
 
@@ -46,14 +58,19 @@ class ModelCase:
 class EvaluationConfig:
     model_name: str
 
-    def get_model_args(self) -> str:
-        return (
-            f"pretrained={self.model_name},"
-            "tensor_parallel_size=4,dtype=auto,gpu_memory_utilization=0.9,trust_remote_code=False"
-        )
-
-
-EXPECTED_ACCURACIES = {"arc_challenge": 0.20}
+    def get_model_args(self, tp_size: int):
+        return {
+            "pretrained": self.model_name,
+            "chat_template_args": {"reasoning_effort": "low"},
+            "enable_thinking": True,
+            "think_end_token": "200008",
+            "tensor_parallel_size": tp_size,
+            "dtype": "auto",
+            "gpu_memory_utilization": 0.95,
+            "trust_remote_code": False,
+            "enable_prefix_caching": False,
+            "enforce_eager": False,
+        }
 
 
 @pytest.mark.skipif(not QUARK_MXFP4_AVAILABLE, reason="amd-quark>=0.9 is not available")
@@ -61,19 +78,32 @@ EXPECTED_ACCURACIES = {"arc_challenge": 0.20}
     not HF_HUB_AMD_ORG_ACCESS,
     reason="Read access to huggingface.co/amd is required for this test.",
 )
-@pytest.mark.parametrize("model_name", MODEL_NAMES)
-@pytest.mark.parametrize("task_name, expected_accuracy", EXPECTED_ACCURACIES.items())
+@pytest.mark.parametrize("tp_size", [1, 2, 4, 8])
+@pytest.mark.parametrize("model_name, expected_accuracy", MODEL_ACCURACIES.items())
 def test_gpt_oss_attention_quantization(
-    model_name: str, task_name: str, expected_accuracy: float
+    model_name: str, tp_size: int, expected_accuracy: float
 ):
-    measured_accuracy = lm_eval.simple_evaluate(
+    model_args = EvaluationConfig(model_name).get_model_args(tp_size)
+
+    extra_run_kwargs = {
+        "gen_kwargs": {"max_gen_toks": 8000},
+        "apply_chat_template": True,
+        "fewshot_as_multiturn": True,
+        "num_fewshot": 5,
+    }
+
+    lm_eval_out = lm_eval.simple_evaluate(
         model="vllm",
-        model_args=EvaluationConfig(model_name).get_model_args(),
-        tasks=task_name,
+        model_args=model_args,
+        tasks="gsm8k_platinum",
         batch_size="auto",
-    )["results"][task_name]["acc,none"]
+        **extra_run_kwargs,
+    )
+    measured_accuracy = float(
+        lm_eval_out["results"]["gsm8k_platinum"]["exact_match,flexible-extract"]
+    )
 
-    rtol = 0.05
+    rtol = 0.02
     assert (
         measured_accuracy - rtol < expected_accuracy
         and measured_accuracy + rtol > expected_accuracy

vllm/model_executor/layers/fused_moe/config.py

@@ -386,6 +386,10 @@ class FusedMoEQuantConfig:
     def use_nvfp4_w4a4(self) -> bool:
         return self.quant_dtype == "nvfp4"
 
+    @property
+    def use_mxfp4_w4a8(self) -> bool:
+        return self._a1.dtype == "fp8" and self._w1.dtype == "mxfp4"
+
     def config_name(self, dtype: torch.dtype) -> str | None:
         """
         Return a string used to construct the filename that contains the
@@ -532,6 +536,8 @@ def fp8_w8a8_moe_quant_config(
     w2_scale: torch.Tensor,
     a1_scale: torch.Tensor | None = None,
     a2_scale: torch.Tensor | None = None,
+    w1_bias: torch.Tensor | None = None,
+    w2_bias: torch.Tensor | None = None,
     per_act_token_quant: bool = False,
     per_out_ch_quant: bool = False,
     block_shape: list[int] | None = None,
@@ -549,6 +555,8 @@ def fp8_w8a8_moe_quant_config(
         g1_alphas=g1_alphas,
         w2_scale=w2_scale,
         g2_alphas=g2_alphas,
+        w1_bias=w1_bias,
+        w2_bias=w2_bias,
         a1_scale=a1_scale,
         a1_gscale=a1_gscale,
         a2_scale=a2_scale,
@@ -564,6 +572,8 @@ def int8_w8a8_moe_quant_config(
     w2_scale: torch.Tensor,
     a1_scale: torch.Tensor | None,
     a2_scale: torch.Tensor | None,
+    w1_bias: torch.Tensor | None = None,
+    w2_bias: torch.Tensor | None = None,
     per_act_token_quant: bool = False,
 ) -> FusedMoEQuantConfig:
     """
@@ -575,6 +585,8 @@ def int8_w8a8_moe_quant_config(
         w2_scale=w2_scale,
         a1_scale=a1_scale,
         a2_scale=a2_scale,
+        w1_bias=w1_bias,
+        w2_bias=w2_bias,
         per_act_token_quant=per_act_token_quant,
         per_out_ch_quant=False,
         block_shape=None,
@@ -654,6 +666,26 @@ def mxfp4_mxfp8_moe_quant_config(
     )
 
 
+def mxfp4_w4a8_moe_quant_config(
+    w1_scale: Union[torch.Tensor, "PrecisionConfig"],
+    w2_scale: Union[torch.Tensor, "PrecisionConfig"],
+    a1_scale: torch.Tensor | None = None,
+    a2_scale: torch.Tensor | None = None,
+    w1_bias: torch.Tensor | None = None,
+    w2_bias: torch.Tensor | None = None,
+    block_shape: list[int] | None = None,
+) -> FusedMoEQuantConfig:
+    """
+    Construct a quant config for fp8 activations and mxfp4 weights.
+    """
+    return FusedMoEQuantConfig(
+        _a1=FusedMoEQuantDesc("fp8", None, a1_scale, None, None, None),
+        _a2=FusedMoEQuantDesc("fp8", None, a2_scale, None, None, None),
+        _w1=FusedMoEQuantDesc("mxfp4", None, w1_scale, None, None, w1_bias),
+        _w2=FusedMoEQuantDesc("mxfp4", None, w2_scale, None, None, w2_bias),
+    )
+
+
 def ocp_mx_moe_quant_config(
     quant_dtype: str,
     w1_scale: Union[torch.Tensor, "PrecisionConfig"],
@@ -691,6 +723,8 @@ def nvfp4_moe_quant_config(
     a2_gscale: torch.Tensor,
     w1_scale: torch.Tensor,
     w2_scale: torch.Tensor,
+    w1_bias: torch.Tensor | None = None,
+    w2_bias: torch.Tensor | None = None,
 ) -> FusedMoEQuantConfig:
     """
     Construct a quant config for mxfp4 activations and nvp4 weights.
@@ -699,6 +733,8 @@ def nvfp4_moe_quant_config(
         "nvfp4",
         w1_scale=w1_scale,
         w2_scale=w2_scale,
+        w1_bias=w1_bias,
+        w2_bias=w2_bias,
         a1_gscale=a1_gscale,
         a2_gscale=a2_gscale,
         g1_alphas=g1_alphas,

vllm/model_executor/layers/fused_moe/fused_moe.py

@@ -38,7 +38,6 @@ from vllm.model_executor.layers.fused_moe.utils import (
 )
 from vllm.model_executor.layers.quantization.utils.mxfp4_utils import dequant_mxfp4
 from vllm.model_executor.layers.quantization.utils.mxfp6_utils import dequant_mxfp6
-from vllm.model_executor.layers.quantization.utils.ocp_mx_utils import OCP_MX_Scheme
 from vllm.model_executor.layers.quantization.utils.quant_utils import (
     QuantKey,
     kFp8Dynamic128Sym,
@@ -1583,6 +1582,11 @@ def _get_config_quant_dtype(
         return "mxfp6_e3m2"
     elif ocp_mx_scheme in {"w_mxfp4_a_mxfp6_e2m3", "w_mxfp6_e2m3_a_mxfp6_e2m3"}:
         return "mxfp6_e2m3"
+    elif ocp_mx_scheme in {"w_mxfp4", "w_mxfp6_e3m2", "w_mxfp6_e2m3"}:
+        return torch.bfloat16
+    elif ocp_mx_scheme in {"w_mxfp4_a_fp8", "w_mxfp6_e3m2_a_fp8", "w_mxfp6_e2m3_a_fp8"}:
+        return torch.float8_e4m3fn
+
     return None
 
 
@@ -1617,17 +1621,10 @@ def fused_experts_impl(
     if use_int4_w4a16:
         assert hidden_states.size(1) // 2 == w1.size(2), "Hidden size mismatch"
     elif ocp_mx_scheme is not None:
-        if ocp_mx_scheme in {
-            "w_mxfp4_a_mxfp4",
-            "w_mxfp4_a_mxfp6_e3m2",
-            "w_mxfp4_a_mxfp6_e2m3",
-        }:
+        if ocp_mx_scheme.startswith("w_mxfp4"):
             # 16bit activation and fp4x2 packed weight
             assert hidden_states.size(1) == w1.size(2) * 2, "hidden size mismatch"
-        elif ocp_mx_scheme in {
-            "w_mxfp6_e3m2_a_mxfp6_e3m2",
-            "w_mxfp6_e2m3_a_mxfp6_e2m3",
-        }:
+        elif ocp_mx_scheme.startswith("w_mxfp6"):
             assert hidden_states.size(1) == (w1.size(2) * 4) // 3, (
                 "hidden size mismatch"
             )
@@ -1717,17 +1714,13 @@ def fused_experts_impl(
         # TODO: On platforms for which `current_platform.supports_mx()` is True
         # and for which we have a native OCP mx fused MOE kernel,
         # this dequantization step should not be done.
-        if ocp_mx_scheme in {
-            OCP_MX_Scheme.w_mxfp4_a_mxfp4,
-            OCP_MX_Scheme.w_mxfp4_a_mxfp6_e3m2,
-            OCP_MX_Scheme.w_mxfp4_a_mxfp6_e2m3,
-        }:
+        if ocp_mx_scheme.startswith("w_mxfp4"):
             # Weight has to be dequantized for mxfp4 emulation.
             w1 = dequant_mxfp4(w1, w1_scale, hidden_states.dtype)
             w1_scale = None
             w2 = dequant_mxfp4(w2, w2_scale, hidden_states.dtype)
             w2_scale = None
-        elif ocp_mx_scheme == OCP_MX_Scheme.w_mxfp6_e3m2_a_mxfp6_e3m2:
+        elif ocp_mx_scheme.startswith("w_mxfp6_e3m2"):
             w1 = dequant_mxfp6(
                 w1, w1_scale, quant_dtype="fp6_e3m2", float_dtype=hidden_states.dtype
             )
@@ -1736,7 +1729,7 @@ def fused_experts_impl(
                 w2, w2_scale, quant_dtype="fp6_e3m2", float_dtype=hidden_states.dtype
             )
             w2_scale = None
-        elif ocp_mx_scheme == OCP_MX_Scheme.w_mxfp6_e2m3_a_mxfp6_e2m3:
+        elif ocp_mx_scheme.startswith("w_mxfp6_e2m3"):
             w1 = dequant_mxfp6(
                 w1, w1_scale, quant_dtype="fp6_e2m3", float_dtype=hidden_states.dtype
             )
@@ -1779,6 +1772,7 @@ def fused_experts_impl(
             quant_dtype=quant_dtype,
             per_act_token_quant=per_channel_quant,
             block_shape=block_shape,
+            ocp_mx_scheme=ocp_mx_scheme,
         )
 
         # SPARSITY_FACTOR is a heuristic margin ensuring tokens_in_chunk * top_k
@@ -1846,6 +1840,7 @@ def fused_experts_impl(
             quant_dtype=quant_dtype,
             per_act_token_quant=per_channel_quant,
             block_shape=block_shape,
+            ocp_mx_scheme=ocp_mx_scheme,
         )
 
         if expert_map is not None:

vllm/model_executor/layers/fused_moe/layer.py

@@ -221,12 +221,14 @@ def get_compressed_expert_map(expert_map: torch.Tensor) -> str:
     )
 
 
+# TODO(rob): move this down to the kernel.
 def maybe_roundup_hidden_size(
     hidden_size: int,
     act_dtype: torch.dtype,
-    quant_config: QuantizationConfig | None,
     moe_parallel_config: FusedMoEParallelConfig,
     is_lora_enabled: bool,
+    model_type: str | None,
+    is_mxfp4_quant: bool,
 ) -> int:
     """
     Given layer hidden size and MoE configurations, round up hidden_size
@@ -235,11 +237,12 @@ def maybe_roundup_hidden_size(
     Args:
         hidden_size: Layer hidden-size
         act_dtype: Data type of the layer activations.
-        quant_config: Fused MoE quantization configuration.
         moe_parallel_config: Fused MoE parallelization strategy configuration.
         is_lora_enabled: True if the engine is enabled with LoRA. This
             is used in the case of mxfp4 quantization in selecting the
             MxFP4Backend.
+        model_type: for checking if gpt-oss
+        is_mxfp4_quant: whether the layer is quantized with mxfp4
 
     Return:
         Rounded up hidden_size if rounding up is required based on the configs.
@@ -254,7 +257,7 @@ def maybe_roundup_hidden_size(
     )
 
     # we are padding globally so EP buffer allocation works
-    if quant_config and quant_config.get_name() == "mxfp4":
+    if model_type == "gpt_oss" and is_mxfp4_quant:
         from vllm.model_executor.layers.quantization.mxfp4 import (
             Mxfp4Backend,
             get_mxfp4_backend,
@@ -398,15 +401,6 @@ class FusedMoE(CustomOp):
         # Expert mapping used in self.load_weights
         self.expert_mapping = expert_mapping
 
-        # Round up hidden size if needed.
-        hidden_size = maybe_roundup_hidden_size(
-            hidden_size,
-            moe_in_dtype,
-            quant_config,
-            self.moe_parallel_config,
-            is_lora_enabled=self.vllm_config.lora_config is not None,
-        )
-
         # For smuggling this layer into the fused moe custom op
         compilation_config = vllm_config.compilation_config
         if prefix in compilation_config.static_forward_context:
@@ -508,7 +502,6 @@ class FusedMoE(CustomOp):
             ), "Aiter Fused MoE kernel only supports expert_map with 0 and 1s."
 
         assert intermediate_size % self.tp_size == 0
-        self.hidden_size = hidden_size
         self.intermediate_size_per_partition = intermediate_size // self.tp_size
         self.reduce_results = reduce_results
         self.renormalize = renormalize
@@ -548,6 +541,24 @@ class FusedMoE(CustomOp):
         )
         self.routing_method_type: RoutingMethodType = self.router.routing_method_type
 
+        # Round up hidden size before creating moe_config.
+        # This way moe_config is created with the correct hidden_size from the start.
+        hidden_size = maybe_roundup_hidden_size(
+            hidden_size=hidden_size,
+            act_dtype=moe_in_dtype,
+            moe_parallel_config=self.moe_parallel_config,
+            is_lora_enabled=vllm_config.lora_config is not None,
+            model_type=(
+                self.vllm_config.model_config.hf_config.model_type
+                if self.vllm_config.model_config is not None
+                else None
+            ),
+            is_mxfp4_quant=(
+                quant_config is not None and quant_config.is_mxfp4_quant(prefix, self)
+            ),
+        )
+        self.hidden_size = hidden_size
+
         self.moe_config: FusedMoEConfig = FusedMoEConfig(
             num_experts=self.global_num_experts,
             experts_per_token=top_k,

vllm/model_executor/layers/fused_moe/utils.py

@@ -23,6 +23,9 @@ from vllm.model_executor.layers.quantization.utils.mxfp6_utils import (
 from vllm.model_executor.layers.quantization.utils.mxfp8_utils import (
     mxfp8_e4m3_quantize,
 )
+from vllm.model_executor.layers.quantization.utils.w8a8_utils import (
+    per_tensor_dequantize,
+)
 from vllm.triton_utils import tl, triton
 from vllm.utils.math_utils import cdiv
 from vllm.utils.torch_utils import is_torch_equal_or_newer
@@ -241,7 +244,27 @@ def moe_kernel_quantize_input(
     per_act_token_quant: bool,
     block_shape: list[int] | None = None,
     is_fp4_scale_swizzled: bool = True,
+    ocp_mx_scheme: str | None = None,
 ) -> tuple[torch.Tensor, torch.Tensor | None]:
+    # Handle OCP MX scheme that requires QDQ (quantize-dequantize) for emulation
+    if ocp_mx_scheme is not None:
+        if ocp_mx_scheme in {"w_mxfp4", "w_mxfp4_a_mxfp4"}:
+            pass  # No QDQ needed for these schemes
+        elif ocp_mx_scheme.endswith("a_fp8"):
+            # Perform QDQ (quantize and dequantize) on activation for emulation
+            # purpose, because there is no native kernel for weight in ocp_mx_scheme
+            # and activation in FP8. The implementation is based on existing
+            # non-emulation ops.
+            qA, qA_scale = ops.scaled_fp8_quant(
+                A, A_scale, use_per_token_if_dynamic=False
+            )
+            A = per_tensor_dequantize(qA, qA_scale).to(A.dtype)
+            # After QDQ, we don't need further quantization
+            return A, None
+        # else: For other schemes (e.g., *_a_mxfp6_e3m2, *_a_mxfp6_e2m3),
+        # weights are already dequantized, and we proceed with normal
+        # activation quantization below.
+
     if quant_dtype == torch.float8_e4m3fn:
         return _fp8_quantize(A, A_scale, per_act_token_quant, block_shape)
     elif quant_dtype == torch.int8:

vllm/model_executor/layers/quantization/base_config.py

@@ -168,3 +168,19 @@ class QuantizationConfig(ABC):
         Interface to update values after config initialization.
         """
         pass
+
+    def is_mxfp4_quant(self, prefix: str, layer: torch.nn.Module) -> bool:
+        """
+        Determine if mxfp4 quantization will be used for this config.
+
+        This allows hidden_size rounding to happen before moe_config creation
+        without needing to instantiate quant_method first.
+
+        Args:
+            prefix: The layer prefix/name in the model
+            layer: The layer module
+
+        Returns:
+            True if this config uses MXFP4 quantization, False otherwise
+        """
+        return False

vllm/model_executor/layers/quantization/mxfp4.py

@@ -229,10 +229,15 @@ class Mxfp4Config(QuantizationConfig):
             )
         return None
 
+    def is_mxfp4_quant(self, prefix: str, layer: torch.nn.Module) -> bool:
+        """MXFP4 config always uses MXFP4 quantization."""
+        return True
+
 
 class Mxfp4MoEMethod(FusedMoEMethodBase):
     def __init__(self, moe: FusedMoEConfig):
         super().__init__(moe)
+        self.weight_dtype = "mxfp4"
         self.mxfp4_backend = get_mxfp4_backend(moe.is_lora_enabled)
 
         self.marlin_input_dtype = None

vllm/model_executor/layers/quantization/quark/quark.py

@@ -320,38 +320,45 @@ class QuarkConfig(QuantizationConfig):
         # Only symmetric weight quantization supported.
         return is_int8_dtype and is_tensor and is_weight_symmetric and is_static
 
-    def _is_ocp_mx(
-        self,
-        weight_quant: dict[str, Any] | None,
-        input_quant: dict[str, Any] | None,
+    def _is_w_ocp_mx_a_x(
+        self, weight_quant: dict[str, Any] | None, input_quant: dict[str, Any] | None
     ) -> bool:
-        # Confirm weights and input quantized.
-        if weight_quant is None or input_quant is None:
+        """
+        This check returns True only if it is an OCP-MX weight quantization.
+        The activation can be any data type (e.g., FP16/BF16, FP8, or OCP-MX format).
+        The rationale for checking only the weight type is that
+        the model loading concept and process primarily concerns the weights themselves.
+        """
+        # Confirm weights quantized.
+        if weight_quant is None:
             logger.debug(
-                "Quark model is not in OCP MX format: "
-                "weight_quant or input_quant not set"
+                "Quark model's weight quantization is incompatible with OCP_MX format: "
+                "weight_quant is not set."
             )
             return False
 
         # Input and weight qscheme needs to be per group.
-        if (
-            weight_quant.get("qscheme") != "per_group"
-            or input_quant.get("qscheme") != "per_group"
-        ):
-            logger.debug("Quark model is not in OCP MX format: not per_group")
+        if weight_quant.get("qscheme") != "per_group":
+            logger.debug(
+                "Quark model's weight quantization is incompatible with OCP MX format: "
+                "weight is not per_group."
+            )
             return False
 
         # Input and weight group size needs to be 32.
-        if weight_quant.get("group_size") != 32 or input_quant.get("group_size") != 32:
-            logger.debug("Quark model is not in OCP MX format: not group_size=32")
+        if weight_quant.get("group_size") != 32:
+            logger.debug(
+                "Quark model's weight quantization is incompatible with OCP MX format: "
+                "group_size of weight is not 32."
+            )
             return False
 
         # Activations and weight scales need to be in e8m0 format.
-        if (
-            weight_quant.get("scale_format") != "e8m0"
-            or input_quant.get("scale_format") != "e8m0"
-        ):
-            logger.debug("Quark model is not in OCP MX format: not scale_format e8m0")
+        if weight_quant.get("scale_format") != "e8m0":
+            logger.debug(
+                "Quark model's weight quantization is incompatible with OCP MX format: "
+                "scale_format of weight is not e8m0."
+            )
             return False
 
         # Input and weight dtypes need to be any of fp4,
@@ -360,14 +367,31 @@ class QuarkConfig(QuantizationConfig):
             "fp4",
             "fp6_e3m2",
             "fp6_e2m3",
-        } or input_quant.get("dtype") not in {"fp4", "fp6_e3m2", "fp6_e2m3"}:
+        }:
             logger.debug(
-                "Quark model is not in OCP MX format: dtype not fp4, fp6_e3m2, fp6_e2m3"
+                "Quark model's weight quantization is incompatible with OCP MX format: "
+                "dtype is not in {fp4, fp6_e3m2, fp6_e2m3}."
             )
             return False
 
         return True
 
+    def is_mxfp4_quant(self, prefix: str, layer: torch.nn.Module) -> bool:
+        """
+        For Quark, determine if it's OCP MXFP4 by checking config directly.
+        This allows hidden_size rounding to happen before moe_config creation.
+        """
+        layer_quant_config = self._find_matched_config(prefix, layer)
+        weight_config = layer_quant_config.get("weight")
+        input_config = layer_quant_config.get("input_tensors")
+
+        return (
+            self._is_w_ocp_mx_a_x(weight_config, input_config)
+            and weight_config is not None
+            and weight_config.get("dtype") == "fp4"
+            and getattr(torch, "float4_e2m1fn_x2", None) is not None
+        )
+
     def _find_matched_config(
         self, layer_name: str, module: torch.nn.Module
     ) -> dict[str, Any]:
@@ -441,7 +465,7 @@ class QuarkConfig(QuantizationConfig):
                 is_static_input_scheme=True,
                 input_symmetric=input_config.get("symmetric"),
             )
-        elif self._is_ocp_mx(weight_config, input_config):
+        elif self._is_w_ocp_mx_a_x(weight_config, input_config):
             return QuarkOCP_MX(weight_config, input_config)
 
         raise NotImplementedError(

vllm/model_executor/layers/quantization/utils/ocp_mx_utils.py

@@ -20,26 +20,44 @@ SUPPORTED_OCP_MX_DTYPES = {"mxfp4", "mxfp6_e3m2", "mxfp6_e2m3"}
 
 
 class OCP_MX_Scheme(str, Enum):
+    w_mxfp4 = "w_mxfp4"
     w_mxfp4_a_mxfp4 = "w_mxfp4_a_mxfp4"
     w_mxfp4_a_mxfp6_e3m2 = "w_mxfp4_a_mxfp6_e3m2"
     w_mxfp4_a_mxfp6_e2m3 = "w_mxfp4_a_mxfp6_e2m3"
+    w_mxfp4_a_fp8 = "w_mxfp4_a_fp8"
+    w_mxfp6_e3m2 = "w_mxfp6_e3m2"
     w_mxfp6_e3m2_a_mxfp6_e3m2 = "w_mxfp6_e3m2_a_mxfp6_e3m2"
+    w_mxfp6_e3m2_a_fp8 = "w_mxfp6_e3m2_a_fp8"
+    w_mxfp6_e2m3 = "w_mxfp6_e2m3"
     w_mxfp6_e2m3_a_mxfp6_e2m3 = "w_mxfp6_e2m3_a_mxfp6_e2m3"
+    w_mxfp6_e2m3_a_fp8 = "w_mxfp6_e2m3_a_fp8"
 
     @classmethod
     def from_quant_dtype(cls, input_dtype: str | None, weight_dtype: str | None):
-        if input_dtype not in OCP_MX_DTYPES or weight_dtype not in OCP_MX_DTYPES:
+        if input_dtype not in OCP_MX_DTYPES and weight_dtype not in OCP_MX_DTYPES:
             return None
+        elif input_dtype is None and weight_dtype == "mxfp4":
+            return cls.w_mxfp4
+        elif input_dtype is None and weight_dtype == "mxfp6_e3m2":
+            return cls.w_mxfp6_e3m2
+        elif input_dtype is None and weight_dtype == "mxfp6_e2m3":
+            return cls.w_mxfp6_e2m3
         elif input_dtype == "mxfp4" and weight_dtype == "mxfp4":
             return cls.w_mxfp4_a_mxfp4
         elif input_dtype == "mxfp6_e3m2" and weight_dtype == "mxfp4":
             return cls.w_mxfp4_a_mxfp6_e3m2
         elif input_dtype == "mxfp6_e2m3" and weight_dtype == "mxfp4":
             return cls.w_mxfp4_a_mxfp6_e2m3
+        elif input_dtype == "fp8" and weight_dtype == "mxfp4":
+            return cls.w_mxfp4_a_fp8
         elif input_dtype == "mxfp6_e3m2" and weight_dtype == "mxfp6_e3m2":
             return cls.w_mxfp6_e3m2_a_mxfp6_e3m2
+        elif input_dtype == "fp8" and weight_dtype == "mxfp6_e3m2":
+            return cls.w_mxfp6_e3m2_a_fp8
         elif input_dtype == "mxfp6_e2m3" and weight_dtype == "mxfp6_e2m3":
             return cls.w_mxfp6_e2m3_a_mxfp6_e2m3
+        elif input_dtype == "fp8" and weight_dtype == "mxfp6_e2m3":
+            return cls.w_mxfp6_e2m3_a_fp8
         else:
             logger.warning(
                 "input_dtype='%s' and"