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Date: Thu, 28 Apr 2005 17:50:26 +0100
From: Bruce M Simpson <bms@spc.org>
To: Maksim Yevmenkin <maksim.yevmenkin@savvis.net>
Message-ID: <20050428165026.GG747@empiric.icir.org>
References: <20050428135120.GB21428@cell.sick.ru>
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cc: jmg@FreeBSD.org
cc: Sten Spans <sten@blinkenlights.nl>
cc: Gleb Smirnoff <glebius@FreeBSD.org>
cc: harti@FreeBSD.org
cc: net@FreeBSD.org
Subject: Re: if_tap unaligned access problem
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On Thu, Apr 28, 2005 at 09:39:27AM -0700, Maksim Yevmenkin wrote:
> you probably should file pr. (1) and (2) above are quick fixes. (3) is 
> more complicated and, maybe, not desirable.

3) may be good. I have an ATM driver which may need this behaviour. I
haven't had a chance to get test coverage on a non-i386 platform so it's
entirely possible that unaligned accesses are happening further up in
netinet land (after coming up from the driver, into netnatm, and into
IP land).

jmg's suggestion of bringing in the NetBSD patches to allow the entire
network stack to be compiled with unaligned accesses (for those platforms
which support it) is interesting because it can simplify or eliminate
some of the acrobatics needed in network drivers to deal with the mbuf
alignment.

Though I'd like to know what Harti thinks re netnatm.

Regards,
BMS