From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [PATCH] Add JMEMCMP to Berkeley Packet Filters
Date: Thu, 10 Feb 2011 14:24:52 +0100
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Cc: netdev@vger.kernel.org, rdunlap@xenotime.net, isdn@linux-pingi.de,
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To: Ian Molton <ian.molton@collabora.co.uk>
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Le jeudi 10 f=C3=A9vrier 2011 =C3=A0 12:31 +0000, Ian Molton a =C3=A9cr=
it :
> This patch allows a data section to be specified for BPF.
>=20
> This is made use of by a MEMCMP like instruction.
>=20
> Testsuite here:
> http://git.collabora.co.uk/?p=3Duser/ian/check-bpf.git;a=3Dsummary
>=20
> Issues:
> * Do I need to update the headers for all arches, or just generic
> * Can sk_run_filter() be called in a context where kmalloc(GFP_KERNEL=
) is
>   not allowed (I think not)

You cannot use GFP_KERNEL in sk_run_filter() : We run in {soft}irq mode=
,
in input path.

> * Data section allocated with second call to sock_kmalloc().
> * Should the patch be broken into two - one to add the data uploading=
,
>   one to add the JMEMCMP insn. ?

May I ask why it is needed at all ?

Then, why only one JMEMCMP would be allowed in a filter ?