A high-throughput and memory-efficient inference and serving engine for LLMs
Mirrored from https://github.com/tduncan-lum/Nvidia-Optimization-Stack---VLLM.git
Synced Nov 6, 02:00 UTC
[Bugfix][ROCm][MoE] Fix mxfp4 oracle regressions from #37128 (#37787)
Signed-off-by: Andreas Karatzas <akaratza@amd.com>
Andreas Karatzas committed
Mar 24, 2026 at 19:17 UTC
679c6a3eccfadb5f80957801f1b6a0c9e8cc9b41
11 files changed
+69
-15
.buildkite/test-amd.yaml
+1
@@ -2526,6 +2526,7 @@ steps:
2526
- pytest -v -s -x lora/test_llm_with_multi_loras.py
2527
- pytest -v -s -x lora/test_olmoe_tp.py
2528
- pytest -v -s -x lora/test_gptoss_tp.py
2529
+ - pytest -v -s -x lora/test_qwen35_densemoel_lora.py
2530
2531
2532
- label: Weight Loading Multiple GPU # 7.5m
tests/lora/test_gptoss_tp.py
+11
@@ -5,6 +5,7 @@ import pytest
5
6
import vllm
7
from vllm.lora.request import LoRARequest
8
+from vllm.platforms import current_platform
9
10
from ..utils import multi_gpu_test
11
@@ -69,6 +70,16 @@ def generate_and_test(llm: vllm.LLM, lora_path: str, lora_id: int) -> None:
70
assert generated_texts[i].startswith(EXPECTED_LORA_OUTPUT[i])
71
72
73
+@pytest.mark.skipif(
74
+ not current_platform.is_cuda(),
75
+ reason=(
76
+ "Mxfp4 LoRA on ROCm is blocked by a spawn compatibility issue. "
77
+ "The fused_moe_lora Triton kernel crashes in spawned subprocesses, "
78
+ "and vLLM forces spawn mode when HIP is initialized before "
79
+ "multiprocessing. Fixing this requires either making the LoRA "
80
+ "Triton kernel spawn-safe or pre-warming the kernel cache."
81
+ ),
82
+)
83
@pytest.mark.parametrize("mxfp4_use_marlin", [True, False])
84
@pytest.mark.parametrize("specialize_active_lora", [True, False])
85
def test_gpt_oss_lora(
vllm/lora/layers/fused_moe.py
+2
-2
@@ -109,8 +109,8 @@ class FusedMoEWithLoRA(BaseLayerWithLoRA):
109
else: # fall back to the default config
110
get_config_func = functools.partial(
111
try_get_optimal_moe_lora_config,
112
- w1_shape=layer.w13_weight.size(),
113
- w2_shape=layer.w2_weight.size(),
112
+ w1_shape=layer.w13_weight.shape,
113
+ w2_shape=layer.w2_weight.shape,
114
rank=rank,
115
top_k=top_k,
116
dtype=config_dtype,
vllm/lora/ops/triton_ops/fused_moe_lora_op.py
+5
-1
@@ -379,7 +379,11 @@ def _fused_moe_lora_kernel(
379
)
380
a_ptrs += BLOCK_SIZE_K * SPLIT_K * stride_ak
381
382
- accumulator += tl.dot(a, b)
382
+ # Cast operands to matching dtype for tl.dot. On ROCm, Triton's
383
+ # compiler may infer different types for a and b when merging
384
+ # if/else branches (TMA desc path returns fp32, tl.load returns
385
+ # the pointer's element type).
386
+ accumulator += tl.dot(a.to(tl.bfloat16), b.to(tl.bfloat16))
387
388
if MUL_ROUTED_WEIGHT:
389
moe_weight = tl.load(topk_weights_ptr + offs_token, mask=token_mask, other=0.0)
vllm/model_executor/layers/fused_moe/config.py
+3
@@ -229,6 +229,9 @@ class FusedMoEQuantConfig:
229
_w1: FusedMoEQuantDesc
230
_w2: FusedMoEQuantDesc
231
is_nvfp4_scale_swizzled: bool = True
232
+ # CK MXFP4 (gfx950) padding info for rocm_aiter_ops.fused_moe()
233
+ hidden_pad: int = 0
234
+ intermediate_pad: int = 0
235
236
def __post_init__(self):
237
assert not self.per_act_token_quant or self.block_shape is None, (
vllm/model_executor/layers/fused_moe/gpt_oss_triton_kernels_moe.py
+5
-5
@@ -257,7 +257,7 @@ def triton_kernel_moe_forward(
257
# sparse_logits.indx contains global expert IDs – remap to local.
258
topk_ids = expert_map[sparse_logits.indx.to(torch.long)]
259
topk_weights = sparse_logits.vals
260
- local_num_experts = w1.size(0)
260
+ local_num_experts = w1.shape[0]
261
routing_data, gather_idx, scatter_idx = make_routing_data(
262
topk_ids, topk_weights, local_num_experts
263
)
@@ -604,8 +604,8 @@ class BaseOAITritonExperts(mk.FusedMoEExpertsModular):
604
require a specialized implementation, like MarlinExperts, they are free
605
to override this function.
606
"""
607
- assert w1.dim() == 3 and w2.dim() == 3
608
- E, _, N = w1.size()
607
+ assert len(w1.shape) == 3 and len(w2.shape) == 3
608
+ E, _, N = w1.shape
609
K = a1.size(-1)
610
611
assert a1.dim() == 2
@@ -683,7 +683,7 @@ class OAITritonExperts(BaseOAITritonExperts):
683
if expert_map is not None:
684
topk_ids = expert_map[topk_ids]
685
686
- local_num_experts = w1.size(0)
686
+ local_num_experts = w1.shape[0]
687
if global_num_experts == -1:
688
global_num_experts = local_num_experts
689
@@ -781,7 +781,7 @@ class UnfusedOAITritonExperts(BaseOAITritonExperts):
781
if expert_map is not None:
782
topk_ids = expert_map[topk_ids]
783
784
- local_num_experts = w1.size(0)
784
+ local_num_experts = w1.shape[0]
785
if global_num_experts == -1:
786
global_num_experts = local_num_experts
787
vllm/model_executor/layers/fused_moe/layer.py
+8
-1
@@ -567,6 +567,13 @@ class FusedMoE(CustomOp):
567
# for heuristic purposes, so it must be initialized first.
568
self.quant_method: FusedMoEMethodBase = _get_quant_method()
569
570
+ # Quant methods (e.g. Mxfp4MoEMethod) may round up hidden_dim
571
+ # and intermediate_size in moe_config during __init__. Sync
572
+ # self.hidden_size so downstream consumers (e.g. LoRA) see the
573
+ # padded value.
574
+ if self.moe_config.hidden_dim != self.hidden_size:
575
+ self.hidden_size = self.moe_config.hidden_dim
576
+
577
if not self.moe_config.is_act_and_mul and not current_platform.is_cuda_alike():
578
raise NotImplementedError(
579
"is_act_and_mul=False is supported only for CUDA and ROCm for now"
@@ -586,7 +593,7 @@ class FusedMoE(CustomOp):
593
594
moe_quant_params = {
595
"num_experts": self.local_num_experts,
589
- "hidden_size": hidden_size,
596
+ "hidden_size": self.hidden_size,
597
"unpadded_hidden_size": unpadded_hidden_size,
598
"intermediate_size_per_partition": self.intermediate_size_per_partition,
599
"params_dtype": params_dtype,
vllm/model_executor/layers/fused_moe/modular_kernel.py
+3
-3
@@ -768,8 +768,8 @@ class FusedMoEExpertsModular(FusedMoEExperts):
768
require a specialized implementation, like MarlinExperts, they are free
769
to override this function.
770
"""
771
- assert w1.dim() == 3 and w2.dim() == 3
772
- E, N, _ = w1.size()
771
+ assert len(w1.shape) == 3 and len(w2.shape) == 3
772
+ E, N, _ = w1.shape
773
K = a1.size(-1)
774
775
if a1.dim() == 2:
@@ -1349,7 +1349,7 @@ class FusedMoEKernelModularImpl:
1349
else:
1350
output = torch.empty_like(hidden_states)
1351
1352
- local_num_experts = w1.size(0)
1352
+ local_num_experts = w1.shape[0]
1353
if global_num_experts == -1:
1354
global_num_experts = local_num_experts
1355
vllm/model_executor/layers/fused_moe/oracle/mxfp4.py
+12
-2
@@ -212,7 +212,11 @@ def select_mxfp4_moe_backend(
212
# LoRA: separate experts backend path
213
if config.is_lora_enabled:
214
if not current_platform.is_cuda():
215
- raise NotImplementedError("Mxfp4 LoRA only supported on CUDA Platform.")
215
+ # ROCm: Triton mxfp4 LoRA hits GPU memory faults due to
216
+ # triton_kernels.tensor.Tensor / HIP read-only page issues
217
+ # during weight swizzle and LoRA forward. Needs work from
218
+ # the triton_kernels/aiter side.
219
+ raise NotImplementedError("Mxfp4 LoRA is currently only supported on CUDA.")
220
if envs.VLLM_MXFP4_USE_MARLIN is False and triton_kernels_supported:
221
logger.info_once("Using Triton backend for mxfp4 lora")
222
return Mxfp4MoeBackend.TRITON_UNFUSED, backend_to_kernel_cls(
@@ -775,6 +779,8 @@ def make_mxfp4_moe_quant_config(
779
w2_scale: Union[torch.Tensor, "PrecisionConfig"],
780
w1_bias: torch.Tensor | None = None,
781
w2_bias: torch.Tensor | None = None,
782
+ hidden_pad: int = 0,
783
+ intermediate_pad: int = 0,
784
) -> FusedMoEQuantConfig | None:
785
"""Create a FusedMoEQuantConfig for the given MXFP4 backend."""
786
if mxfp4_backend in (
@@ -796,12 +802,16 @@ def make_mxfp4_moe_quant_config(
802
Mxfp4MoeBackend.FLASHINFER_CUTLASS_MXFP4_BF16,
803
Mxfp4MoeBackend.CK,
804
):
799
- return mxfp4_w4a16_moe_quant_config(
805
+ config = mxfp4_w4a16_moe_quant_config(
806
w1_bias=w1_bias,
807
w2_bias=w2_bias,
808
w1_scale=w1_scale,
809
w2_scale=w2_scale,
810
)
811
+ if mxfp4_backend == Mxfp4MoeBackend.CK:
812
+ config.hidden_pad = hidden_pad
813
+ config.intermediate_pad = intermediate_pad
814
+ return config
815
else:
816
return ocp_mx_moe_quant_config(
817
quant_dtype="mxfp4",
vllm/model_executor/layers/fused_moe/rocm_aiter_fused_moe.py
+11
-1
@@ -292,6 +292,8 @@ def rocm_aiter_fused_experts(
292
doweight_stage1=apply_router_weight_on_input,
293
num_local_tokens=num_local_tokens,
294
output_dtype=output_dtype,
295
+ hidden_pad=quant_config.hidden_pad,
296
+ intermediate_pad=quant_config.intermediate_pad,
297
bias1=quant_config.w1_bias if quant_config.use_mxfp4_w4a16 else None,
298
bias2=quant_config.w2_bias if quant_config.use_mxfp4_w4a16 else None,
299
)
@@ -332,7 +334,15 @@ class AiterExperts(mk.FusedMoEExpertsModular):
334
(kFp8StaticChannelSym, kFp8DynamicTokenSym),
335
(kMxfp4Static, None),
336
]
335
- return (weight_key, activation_key) in SUPPORTED_W_A
337
+ if (weight_key, activation_key) not in SUPPORTED_W_A:
338
+ return False
339
+ # CK MXFP4 MoE kernels are only supported on gfx950.
340
+ if weight_key == kMxfp4Static:
341
+ from vllm.platforms.rocm import on_gfx950
342
+
343
+ if not on_gfx950():
344
+ return False
345
+ return True
346
347
@staticmethod
348
def _supports_activation(activation: MoEActivation) -> bool:
vllm/model_executor/layers/quantization/mxfp4.py
+8
@@ -158,6 +158,12 @@ class Mxfp4MoEMethod(FusedMoEMethodBase):
158
intermediate_size_per_partition_after_pad
159
)
160
161
+ # CK (gfx950) padding info for rocm_aiter_ops.fused_moe()
162
+ self.hidden_pad = extra_weight_attrs.get("hidden_pad", 0)
163
+ self.intermediate_pad = (
164
+ intermediate_size_per_partition_after_pad - intermediate_size_per_partition
165
+ )
166
+
167
# Fused gate_up_proj (column parallel)
168
w13_weight = torch.nn.Parameter(
169
torch.zeros(
@@ -362,6 +368,8 @@ class Mxfp4MoEMethod(FusedMoEMethodBase):
368
w2_scale=w2_scale,
369
w1_bias=w1_bias,
370
w2_bias=w2_bias,
371
+ hidden_pad=self.hidden_pad,
372
+ intermediate_pad=self.intermediate_pad,
373
)
374
375
def select_gemm_impl(