Dear All, I am now reading the kernel code and have some questions, wish somebody can help me. If some questions are too newbie, please forgive. And really want to know why its design like this or that. 1. What is the difference of boot_cpu_data in include/asm-i386/processor.h(by #define cpuinfo_x86 boot_cpu_data), and the one in arch/i386/kernel/head.S(by #define CPU_PARAMS SYMBOL_NAME(boot_cpu_data))? What the "SYMBOL_NAME" defined in assembly language, a memory area? 2. Where are those current_cpu_data fields are assigned value, can somebody give me one example? 3. why need another pgprot structure to store those privilege bit separately, instead of putting them into the directly on the pte? Thanks for your patience. Very much Noah Yan -- Kernelnewbies: Help each other learn about the Linux kernel. Archive: http://mail.nl.linux.org/kernelnewbies/ FAQ: http://kernelnewbies.org/faq/