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Subject: Re: security.bsd.stack_guard_page
To: freebsd-questions@freebsd.org
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From: Anton Yuzhaninov <citrin+bsd@citrin.ru>
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Date: Thu, 9 Mar 2017 10:45:49 -0500
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On 03/09/17 10:26, Andrea Venturoli wrote:
> Any doc on this sysctl?

It seems to be only docs available are sysctl description and commit 
message:
https://svnweb.freebsd.org/changeset/base/215307

> I think I get the overall picture on what it does, but I'd like to
> understand whether there are donwsides on enabling this.
> Like... system running slower or consuming more RAM... incompatible
> ports or drivers... etc.
>
> Any reason not to enable it?

Id don't know for sure, but probably this feature adds a little value 
given that SSP (stack smashing protection) is already enabled for base 
system and most of ports.

If you need definitive answer, try to ask author of this feature (kib@).