---
id: pr-vllm-34577
repo: vllm-project/vllm
pr: 34577
title: '[Bugfix] Rescale NVFP4 weight scales to fix BF16 dequant underflow'
author: ricky-chaoju
date: '2026-03-17'
url: https://github.com/vllm-project/vllm/pull/34577
source_category: upstream-code
architectures:
- sm100
tags:
- fp4
- nvfp4
- quantization
techniques: []
hardware_features:
- fp4
- nvfp4
kernel_types:
- quantization
languages:
- python
captured_at: '2026-04-27'
status: merged
merge_sha: 245758992ed74fbaaffcdb4e607ad817627455fc
inclusion_reason: kernel file changes
changed_paths:
- vllm/model_executor/layers/quantization/utils/marlin_utils_fp4.py
head_ref_oid: 6f71fa9131ec2d357d726fcee8584948f8f06ae3
artifact_dir: evidence/pull-bundles/vllm/gh-34577
---
# [Bugfix] Rescale NVFP4 weight scales to fix BF16 dequant underflow

- Repository: `vllm-project/vllm`
- PR: [34577](https://github.com/vllm-project/vllm/pull/34577)
- Decision: `kernel file changes`
- Reason: kernel file changes

## Changed Paths

- `vllm/model_executor/layers/quantization/utils/marlin_utils_fp4.py`

## Evidence Bundle

`evidence/pull-bundles/vllm/gh-34577`
