On Sat, Sep 1, 2012 at 1:01 PM, Shentino <shent...@gmail.com> wrote: > On Sat, Sep 1, 2012 at 12:30 PM, Xin Tong <xerox.time.t...@gmail.com> wrote: >> When a process is created in Linux, corresponding page table is >> implemented. In the current x86 linux, the page table is a multi-level >> page table and CR3 points to the first level of the page table. I >> have 2 questions. >> >> 1. is the value in CR3 virtual address or physical address ? > > It's a physical address. It points the CPU to it in physical memory. > > More generally, all addresses in page tables, directories, etc are > physical addresses. > >> 2. can the address of the first level of the page table during a >> process's lifetime change ? > > This I don't know. > >> 3. can two different processes have their CR3 being the same value >> even though they have different first level page tables ? > > I'm not sure about this, but I think CR3 is actually bound to the > mm_struct and not the process. > > Think about separate processes with the same address space, such as > multithreaded processes.
Do not all the threads share the same address space in a multithreaded program ? Xin > >> >> Thanks >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in >> the body of a message to majord...@vger.kernel.org >> More majordomo info at http://vger.kernel.org/majordomo-info.html >> Please read the FAQ at http://www.tux.org/lkml/ -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
