linux-2.3 dhd

[David Huggins-Daines]

CVSROOT:	/home/cvs/parisc
Module name:	linux-2.3
Changes by:	dhd	00/09/01 16:23:04

Modified files:
	fs             : Tag: STABLE_2_3_99PRE8 exec.c 

Log message:
If we're going to map in a whole gigabyte of stack space at process
start up, we could at least have the decency to start it at stack_base
so that it has room to grow down (with argv/envp) as well as up.

This probably has unforseen consequences due to the fact that we are
already mapping those pages in put_dirty_page().  Oh well, such is life.

My previous bad hack had the minor problem that, since they were not
actually part of the same vm_area as the stack itself (doh!), the
extra pages allocated under the inital stack pointer were not getting
copied across a fork(), which caused the machine to crash at very
infrequent moments (such as when bootstrapping gcc, natch)

Note that once we get a real dynamically-growable stack we will still
have to be careful about the initial stack frame.  Let this be a warning.