Hi all, thank you all for the answers to my last question! That really did help a lot. I am now trying to define the "struct thread_struct" for my target architecture. I as inspected the code for other architectures, I found there two stack pointers. For intel (i386): esp0 and esp; for Motorola: ksp and usp (the comment here says, these are the kernel stack pointer and user stack pointer; so I guess, esp0 and esp play basically the same role). Unfortunatelly, I couldn't find any explanations (in the books I have) about these two different stacks/stack pointers. Does someone have an idea, what it is all about? I mean, why do I need two separate stack pointers? regards, Paul -- 5 GB Mailbox, 50 FreeSMS http://www.gmx.net/de/go/promail +++ GMX - die erste Adresse für Mail, Message, More +++ -- Kernelnewbies: Help each other learn about the Linux kernel. Archive: http://mail.nl.linux.org/kernelnewbies/ FAQ: http://kernelnewbies.org/faq/