On 3/8/13 6:33 PM, "H. Peter Anvin" <hpa at zytor.com> wrote: >On 03/08/2013 02:06 AM, Jingbai Ma wrote: >> >> Kernel do have some abilities that user space haven't. It's possible to >> map whole memory space of the first kernel into user space on the second >> kernel. But the user space code has to re-implement some parts of the >> kernel memory management system again. And worse, it's architecture >> dependent, more architectures supported, more codes have to be >> implemented. All implementation in user space must be sync to kernel >> implementation. It's may called "flexibility", but it's painful to >> maintain the codes. >> > >What? You are basically talking about /dev/mem... there is nothing >particularly magic about it at all. What we are talking about is filtering memory pages (AKA memory pages classification) The makedumpfile (or any other dumper in user space) has to know the exactly memory layout of the memory management data structures, it not only architecture dependent, but also may varies in different kernel release. At this point, /dev/mem doesn't give any help. So IMHO, I would like to do it in kernel, rather than So keep tracking changes in user space code. > > -hpa > >-- >H. Peter Anvin, Intel Open Source Technology Center >I work for Intel. I don't speak on their behalf. >
