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Date: Thu, 31 Jan 2008 11:29:01 -0700 (MST)
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To: mav@freebsd.org
From: "M. Warner Losh" <imp@bsdimp.com>
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Cc: cvs-src@freebsd.org, src-committers@freebsd.org, cvs-all@freebsd.org
Subject: Re: cvs commit: src/sys/netgraph netgraph.h ng_base.c ng_iface.c
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In message: <200801310851.m0V8pmNB093625@repoman.freebsd.org>
            Alexander Motin <mav@FreeBSD.org> writes:
:  Implement stack protection based on GET_STACK_USAGE() macro.
:  This fixes system panics possible with complicated netgraph setups
:  and allows to avoid unneded extra queueing for stack unwrapping.

How does this help?  What are the units?  The code is almost entirely
opaque given its magic numbers (100?  64?).  Also, if you are checking
to see if the stack usage is too big, it may already be too late.

Warner