In article <20011121142154.A2062@krishna>,
Bang Jun-Young <bjy@mogua.org> wrote:
>would be enough. Also, the comment is wrong:
>
>-		 * not fixed: make sure we skip over the largest possible heap.
>
>0x400000 doesn't belong to the heap. I guess he didn't consider the
>address range below vm_taddr. 

that's certainly true and something that is worth better understanding.
"start" used to live down around 0x1000 or so on most systems.   now
it seems to have moved to around 0x08048110 or so (at least on my i386
systems).

i think this is due to things like this appearing in the ELF ld scripts:
  . = 0x08048000 + SIZEOF_HEADERS;


i would like to know where this magic 0x08048000 number comes from
and what the ~128MB of address space before "start" is supposed to be 
used for now.  does anyone know?


on the one hand, it seems clear to me that what Wine is doing is 
bad form.   on the other hand, irrespective of Wine, it isn't clear
to me that UVM should make efforts protect that leading 128MB as 
part of the text/data area like it currently does.   but i'm not 
sure --- i don't even know why the 128MB gap was put there.


chuck