From d8ca7fee751b676dccfcf3e5dd2a23c2979853e6 Mon Sep 17 00:00:00 2001
From: Shirley125 <54166744+Shirley125@users.noreply.github.com>
Date: Mon, 27 Oct 2025 16:56:09 +0800
Subject: [PATCH] [bugfix][main]fix proxy decode bug (#3750)

### What this PR does / why we need it?

fix proxy decode bug when parsing non-UTF-8 characters.

- vLLM version: v0.11.0
- vLLM main:
https://github.com/vllm-project/vllm/commit/c9461e05a4ed3557cfbf4b15ded1e26761cc39ca

---------

Signed-off-by: CHEN <116010019@link.cuhk.edu.cn>
---
 .../load_balance_proxy_layerwise_server_example.py        | 8 +++++++-
 .../load_balance_proxy_server_example.py                  | 8 +++++++-
 2 files changed, 14 insertions(+), 2 deletions(-)

diff --git a/examples/disaggregated_prefill_v1/load_balance_proxy_layerwise_server_example.py b/examples/disaggregated_prefill_v1/load_balance_proxy_layerwise_server_example.py
index c6001553..7e80b55c 100644
--- a/examples/disaggregated_prefill_v1/load_balance_proxy_layerwise_server_example.py
+++ b/examples/disaggregated_prefill_v1/load_balance_proxy_layerwise_server_example.py
@@ -556,7 +556,13 @@ async def _handle_completions(api: str, request: Request):
                                 instance_info.prefiller_idx,
                                 instance_info.prefiller_score)
                             released_kv = True
-                        chunk_str = chunk.decode("utf-8").strip()
+                        try:
+                            chunk_str = chunk.decode("utf-8").strip()
+                        except UnicodeDecodeError:
+                            logger.debug(
+                                f"Skipping chunk: {chunk}")
+                            yield chunk
+                            continue
                         if not chunk_str:
                             continue
                         if chunk_str.startswith("data: "):
diff --git a/examples/disaggregated_prefill_v1/load_balance_proxy_server_example.py b/examples/disaggregated_prefill_v1/load_balance_proxy_server_example.py
index 880ed69e..0694aced 100644
--- a/examples/disaggregated_prefill_v1/load_balance_proxy_server_example.py
+++ b/examples/disaggregated_prefill_v1/load_balance_proxy_server_example.py
@@ -539,7 +539,13 @@ async def _handle_completions(api: str, request: Request):
                                 instance_info.prefiller_idx,
                                 instance_info.prefiller_score)
                             released_kv = True
-                        chunk_str = chunk.decode("utf-8").strip()
+                        try:
+                            chunk_str = chunk.decode("utf-8").strip()
+                        except UnicodeDecodeError:
+                            logger.debug(
+                                f"Skipping chunk: {chunk}")
+                            yield chunk
+                            continue
                         if not chunk_str:
                             continue
                         if chunk_str.startswith("data: "):