Xiaoyu Xu

The Hong Kong Polytechnic University

LLM Security Machine Unlearning Trustworthy AI

About Me

I am a Ph.D. student at The Hong Kong Polytechnic University, co-supervised by Prof. Haibo Hu and Dr. Minxin Du.

Before starting my Ph.D., I received my B.Eng. in Electronics and Communication Engineering from Sun Yat-sen University (SYSU) in 2024.

Security, privacy, and reliability of large language models (LLMs).

2020.09 - 2024.06, Bachelor of Engineering in Electronics and Communication Engineering, Sun Yat-sen University (SYSU)
2024.09 - Present, Ph.D. student, The Hong Kong Polytechnic University

Rethinking LLM Unlearning: From Safety Constraints to Functional Utility

Xiaoyu Xu, Minxin Du, Li Bai, Junxu Liu, Huadi Zheng, Peizhao Hu, Qingqing Ye, Haibo Hu

Survey (Paper)
When Routine Chats Turn Toxic: Unintended Long-Term State Poisoning in Personalized Agents

Xiaoyu Xu, Minxin Du, Qipeng Xie, Haobin Ke, Qingqing Ye, Haibo Hu

arXiv 2026 (Paper) (Code) (Demo)
FIT to Forget: Robust Continual Unlearning for Large Language Models

Xiaoyu Xu, Minxin Du, Kun Fang, Yaxin Xiao, Zhicong Huang, Cheng Hong, Qingqing Ye, Haibo Hu

arXiv 2026 (Paper) (Code)
From Domains to Instances: Dual-Granularity Data Synthesis for LLM Unlearning

Xiaoyu Xu, Minxin Du, Zitong Li, Zi Liang, Zhibiao Guo, Shiyu Zhang, Peizhao Hu, Qingqing Ye, Haibo Hu

ACL 2026 Findings (Paper) (Code)
Unlearning Isn't Deletion: Investigating Reversibility of Machine Unlearning in LLMs

Xiaoyu Xu, Xiang Yue, Yang Liu, Qingqing Ye, Huadi Zheng, Peizhao Hu, Minxin Du, Haibo Hu

ICML 2026 (Paper) (Code)
OBLIVIATE: Robust and Practical Machine Unlearning for Large Language Models

Xiaoyu Xu, Minxin Du, Qingqing Ye, Haibo Hu

EMNLP 2025 (Paper) (Code)