Re: msync() bug

[Hugh Dickins]

On Mon, 9 Jul 2001, Andrea Arcangeli wrote:
> On Tue, Jul 10, 2001 at 12:43:12AM +1000, Andrew Morton wrote:
> > 
> > Question:  What happens if a program mmap's a part of /dev/mem
> > which passes all of these tests?   Couldn't it then pick some
> 
> that cannot happen, remap_pte_range only maps invalid pages or reserved
> pages.
> 
> > arbitrary member of mem_map[] which may or may not have
> > a non-zero ->mapping?

Anyone know why mmap() of /dev/mem behaves in this way - solves the
problem Andrew raises, but surely that could be solved in a better way?
Seems strange that mmap() cannot give you what read() and write() can.

Hugh