In 264, the Wei general Zhong Hui started a rebellion against Sima Zhao after leading Wei forces to conquer Shu. At the time, Sima Zhao only heard rumours about the rebellion and had no concrete evidence yet. As he had all along treated Zhong Hui well, he was reluctant to believe that Zhong would rebel against him. After Xun Xu cautioned him against trusting Zhong Hui, Sima Zhao led his forces to garrison at Chang'an as a precautionary measure. Guo Yi (郭奕) and Wang Shen (王深) urged Sima Zhao to banish Xun Xu because they feared that he would side with Zhong Hui, given that he was raised by the Zhong family (Zhong Hui was Zhong Yao's son). However, Sima Zhao ignored them and continued to treat Xun Xu as he did before, and even allowed Xun Xu to ride in the same carriage as him. Previously, when Sima Zhao ordered Zhong Hui to lead Wei forces to conquer Shu, Xun Xu had nominated Wei Guan to supervise the campaign. Later, Wei Guan played a huge role in suppressing Zhong Hui's rebellion. After Shu had been pacified, Xun Xu followed Sima Zhao back to the Wei capital, Luoyang, where he, Pei Xiu and Yang Hu were put in charge of the privy council.