The key is the test TST_SEL_RET on line 682. It compares the RPL of the return CS selector (saved on the stack by the original CALL) against the current CPL. If RPL == CPL, the PLA returns 0x000 (continue) and LD_DESCRIPTOR finishes normally -- same-privilege return. If RPL CPL, the caller is returning to a less-privileged ring, so the PLA redirects to 0x686 (RETF_OUTER_LEV) -- the cross-privilege path that must also restore the caller's stack. If RPL
Фото: Patrick Pleul/dpa (Photo by Patrick Pleul/ Picture alliance via Getty Images。关于这个话题，爱思助手下载最新版本提供了深入分析
Антонина Черташ，这一点在服务器推荐中也有详细论述
是囿于一时一事的得失，还是着眼打基础、利长远的实绩？，详情可参考旺商聊官方下载