From mboxrd@z Thu Jan  1 00:00:00 1970
From: Patrick McHardy <kaber@trash.net>
Subject: Re: iptables not working with monolithic 2.6.26.5 kernel on ARM
Date: Sun, 05 Oct 2008 15:24:55 +0200
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Cc: Martin Schwenke <martin@meltin.net>,
	netfilter-devel@vger.kernel.org
To: Jan Engelhardt <jengelh@medozas.de>
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Jan Engelhardt wrote:
> You can change the XT_ALIGN macro in the
> kernel/include/linux/netfilter/x_tables.h and
> iptables/include/linux/netfilter/x_tables.h to read
> 
> 	#ifndef roundup
> 	#define roundup(x, y) ((((x) + ((y) - 1)) / (y)) * (y))
> 	#endif
> 	#define XT_ALIGN(s) roundup(s, sizeof(uint64_t))
> 
> and try again. There might be more alignment issues hiding, so
> don't expect it to fix it all in a magic whizz.

An idea to avoid these problems in the future would be to change
the kernel so it accepts stricter alignment than what we currently
use and after a grace period (maybe 1-2 years) change XT_ALIGN in
userspace so it starts using u64 or simply 8 byte alignment
everywhere.