From owner-freebsd-hackers@FreeBSD.ORG  Sat Mar 15 01:38:59 2014
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Subject: Re: mbuf question
From: Rui Paulo <rpaulo@FreeBSD.org>
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Date: Fri, 14 Mar 2014 18:39:00 -0700
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To: Hooman Fazaeli <hoomanfazaeli@gmail.com>
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On 14 Mar 2014, at 06:20, Hooman Fazaeli <hoomanfazaeli@gmail.com> =
wrote:

> Hi list,
>=20
> Is it safe to use m->m_pktdat area to store some arbitrary data about =
packets allocated as mbuf+cluster pair?

No, because m_pktdat is really MH_databuf which is part of a union with =
MH_ext which is set when you allocate an mbuf cluster.

--
Rui Paulo