---
id: pr-vllm-35271
repo: vllm-project/vllm
pr: 35271
title: '[Feat] Add CUDA torch fallbacks for fp8_mqa_logits/fp8_paged_mqa_logits_torch function'
author: chaunceyjiang
date: '2026-02-28'
url: https://github.com/vllm-project/vllm/pull/35271
source_category: upstream-code
architectures:
- sm90
tags:
- attention_kv
- gemm_quant
- paged attention
- sm90
techniques:
- fine-grained-quantization
hardware_features:
- fp8
- hopper
kernel_types:
- attention
- gemm
- mla
languages:
- cuda-cpp
captured_at: '2026-05-16'
status: merged
merge_sha: 7e08c22b8cb65a1bea6b4bf9c52ed6e71d4acc47
inclusion_reason: Preserve page/KV/layout and plan-run contracts; profile memory traffic separately from math utilization.
changed_paths:
- vllm/model_executor/layers/sparse_attn_indexer.py
- vllm/utils/deep_gemm.py
- vllm/v1/attention/backends/mla/indexer.py
artifact_dir: evidence/pull-bundles/vllm/gh-35271
head_ref_oid: 6ec06669c9a0ff5264697ceafe6f49cafb41cd5d
---
# [Feat] Add CUDA torch fallbacks for fp8_mqa_logits/fp8_paged_mqa_logits_torch function

- Repository: `vllm-project/vllm`
- PR: [35271](https://github.com/vllm-project/vllm/pull/35271)
- Decision: `Preserve page/KV/layout and plan-run contracts; profile memory traffic separately from math utilization.`
- Reason: Preserve page/KV/layout and plan-run contracts; profile memory traffic separately from math utilization.

## Changed Paths

- `vllm/model_executor/layers/sparse_attn_indexer.py`
- `vllm/utils/deep_gemm.py`
- `vllm/v1/attention/backends/mla/indexer.py`

## Evidence Bundle

`evidence/pull-bundles/vllm/gh-35271`
