Waldo Alvarez CaƱizares wrote:
Another thing that could be done is to detect the CPU at some time during initialization and use one of two ntdll (on with SYSCALL an another without it).
It's implemented in WinXP much easier than that. On startup it's detected if the processor supports SYSCALL and the appropriate code is sticked into the user shared page. The user mode code then just does jmp at the place in user shared page and it uses the correct code. Easy ;-)
- Filip