On Sun, Jan 07, 2001 at 07:06:22AM +0000, Charles M. Hannum wrote:

 > > Only include PROT_EXEC in maxprot if the user specified PROT_EXEC
 > > in the mmap() call.  maxprot is used to create device mappings,
 > > and always including PROT_EXEC causes the mapping to fail on the Alpha
 > > when mapping a non-RAM offset of /dev/mem (which may be sparse, so
 > > instruction fetch from there is disallowed).
 > 
 > I believe this change is VERY, VERY WRONG, as it specifically breaks
 > valid usage of mprotect(2).  I wouldn't be at all surprised to find
 > out that it actually breaks some software that does dynamic code
 > compilation.

Also, you should take a look at the actual change (I'm not sure that
you actually did!).  It's a one-liner, in the ((flags & MAP_ANON) == 0)
case of sys_mmap().  Anonymous mappings still get VM_PROT_ALL as the
maxprot.  I should have been more clear about this in my commit message.

-- 
        -- Jason R. Thorpe <thorpej@zembu.com>