Hello... > Could you explain me, what exactly a stack segment is? Is it a memory > range, where the stack data (I mean, something, that I push on the > stack) is saved? yes...a memory range (segment) where stack lives. user stack lives on virtual address less than PAGE_OFFSET, whereas kernel stack can be anywhere on virtual address equal or greater than PAGE_OFFSET. PAGE_OFFSET is a virtual address which split address space into user and kernel space. for the exact virtual address of user space stack, try to dump a task struct of a process and look at the task_struct->mm>start_stack, or simply use "pmap" utility to list VMAs of a process Perhaps you can re-read any books about general programming. There you will find out that stack contains local variable of a function (which is currently running, of course), return address when a function finish and so on. Of course, if you push something explicitly e.g via "push" assembly operation, it will be saved to the stack too. I forget the exact contents, but I hope you got a picture. As Jan Hudec previously said, remember that kernel stack is only 8kb (IIRC now it is 4k, depends on kernel config). That means two things: 1. don't declare too many local variables on function, e.g very long array 2. don't do function call to deep....so something like recursion must be done carefully If you do something that overflow kernel stack, anything can happen. I can only imagine that it can cause memory corruption regards Mulyadi -- Kernelnewbies: Help each other learn about the Linux kernel. Archive: http://mail.nl.linux.org/kernelnewbies/ FAQ: http://kernelnewbies.org/faq/
