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Date: Sun, 2 Mar 2008 15:49:39 +0100
From: Paolo Pisati <piso@FreeBSD.org>
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Cc: freebsd-net@FreeBSD.org
Subject: ipfw initialization: SI_ORDER_ANY -> SI_ORDER_MIDDLE?
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Hi,

i just found out that depending on a KLD doesn't imply any
initialization order, thus depending on a lock initialized in the ipfw
init path is _really_ a bad idea from another KLD init path (see
ip_fw_nat.c::ipfw_nat_init()).

A fix would be to move ipfw init priority from SI_ORDER_ANY to
SI_ORDER_MIDDLE, but i guess there are side effects that i'm
unaware in this modification...

On the other hand, if we keep ipfw at SI_ORDER_ANY, i don't know how
to build stuff that relies on it without opening race conditions:
see ip_fw_nat.c::flush_nat_ptrs() called in rule deletion and
rule configuration paths.

bye,
P.

ps yes, next time i'll better read the MODULE_DEPEND man page...