[libcpu][risc-v] Fix PLIC interrupt processing order

[FurryAcetylCoA]

Description / 描述

This PR fixes the PLIC interrupt handling order in the RISC-V virt64 libcpu. The previous code called plic_complete before executing the interrupt handler, which violated the correct interrupt flow. According to Section 1.5 Interrupt Flow of the RISC-V Platform-Level Interrupt Controller Specification, the interrupt should be handled first and then completed.

本次 PR 修复了 RISC-V virt64 中的 PLIC 中断处理顺序。以往的代码在执行中断 handler 之前调用了 plic_complete。根据 RISC-V Platform-Level Interrupt Controller Specification 的 1.5. Interrupt Flow 节的说明，应当先运行 handler，然后再 complete。

Modified Files / 修改文件

• libcpu/risc-v/virt64/plic.c: Fixed plic_handle_irq by moving plic_complete after the handler call.

[github-actions]

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[github-actions]

📌 Code Review Assignment

🏷️ Tag: libcpu_riscv

Reviewers: @Yaochenger

Changed Files (Click to expand)

• libcpu/risc-v/virt64/plic.c

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📊 Current Review Status (Last Updated: 2026-03-31 20:05 CST)

• ⌛ @Yaochenger Pending Review

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