FreeBSD and DEP aka "NX bit"?

[Robert Watson]

On Wed, 27 Aug 2008, Andrew Reilly wrote:

> On Tue, Aug 26, 2008 at 09:28:07AM -0700, Alfred Perlstein wrote:
>> * Andrew Reilly <andrew-freebsd at areilly.bpc-users.org> [080826 00:51] 
>> wrote:
>>> I've been using 7-STABLE on amd64 for a long time, and haven't noticed any 
>>> problems with Java or SBCL lisp or PLT-scheme, all of which use JIT code 
>>> generation (but probably neither use jemalloc?)
>>
>> mprotect(2)?
>
> Fair enough.  Good to know that it's actually tweaking the NX permissions, I 
> guess.  The man page seems a little vague about when it might succeed, and 
> what effect it might have...

We're behind on the not-mapping-writable stuff, so for better (and worse) 
quite a few such things in application have been faulted in by other operating 
systems already.  That doesn't mean there won't be issues, but does have the 
redeeming aspect that things should be less bumpy for us going forward. 
Hopefully we can start making that progress a bit more quickly...

Robert N M Watson
Computer Laboratory
University of Cambridge