Re: copy_from_user/copy_to_user question

Steven Rostedt
2005-12-03T18:26:29Z

On Sat, 2005-12-03 at 15:35 -0700, Andi Kleen wrote:
> Steven Rostedt <rostedt@goodmis.org> writes:
> >
> > Nope, the kernel is always locked into memory. If you take a page fault
> > from the kernel world, you will crash and burn. The kernel is never
> > "swapped out". So if you are in kernel mode, going into do_page_fault
> > in arch/i386/mm/fault.c there is no path to swap a page in.
>
> Actually there is - when the page fault was caused by *_user.

Sorry I wasn't clearer. I know the copy_user case (and explained it in
detail earlier in this thread). I was talking about what happens in the
memcpy case. So that should have said "outside of copy_user and
friends, there is no path to swap a page in".

-- Steve