Hi, I'm Benjamin and I'm studying the kernel. I write you this email because I've a trouble with the mmu and the virtual memory. I try to understand how a program (user land) can write something into the stack (push ebp, for example), indeed, the program works with virtual address (between 0x00000 and 0x8... if my memory is good) but at the hardware side the address is not the same (that's why mmu was created, if I'm right). My problem is the following : how the data is wrote on the physical memory. When I try a strace (kernel 2.6.32 on a simple program) I have no hint on the transfer of data. Moreover, according to the wikipedia web page on syscall ( https://en.wikipedia.org/wiki/System_call#The_library_as_an_intermediary ), a call is not managed by the kernel. So, how the transfer between virtual memory and physical memory is possible ? I hope my email is understandable, I tried to put words on my troubles. Thanks a lot for your help and have a nice day. Benjamin. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>