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Date: Wed, 15 Oct 2014 15:14:10 +0300
From: Konstantin Belousov <kostikbel@gmail.com>
To: Terry Kennedy <TERRY@tmk.com>
Subject: Re: [rfc] Add boot-time warning messages to PAE kernels
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On Wed, Oct 15, 2014 at 03:35:45AM -0400, Terry Kennedy wrote:
> > PAE is the way to get NX bit on 32bit kernels.
> 
>   Educate me here - is this non-amd64-capable hardware being used in a
> production environment, or amd64-capable hardware being run in i386 mode
> for some reason? I haven't run into any i386 user code that wouldn't run
> on a FreeBSD amd64 kernel, so I'm trying to see why PAE is the desired
> solution here.
I do not understand the question.  One of the reason for PAE existence
at the current times is the ability to get working !PROT_EXEC support
on i386 kernel.  I have no idea about 'production' environments.

WRT user 32bit code which does not run on amd64 kernel, you obviously
did not tried hard.  The compat32 is lacking; the simple (from the PoV
of the kernel facilities used) programs do run, but anything more
involved has a chance to meet unimplemented functionality.

E.g., should pf control considered management interfaces ?  But it is
required for things like miniupnpd and squid in transparent mode.