From mboxrd@z Thu Jan 1 00:00:00 1970 From: Phil Sutter Subject: Re: [PATCH] af_packet: flush complete kernel cache in packet_sendmsg Date: Fri, 2 Sep 2011 15:59:55 +0200 Message-ID: <20110902135954.GA29025@philter> References: <20110505141107.GC30443@orbit.nwl.cc> <1314961686-30870-1-git-send-email-phil.sutter@viprinet.com> <1314971179.3092.159.camel@deadeye> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: linux-arm-kernel@lists.infradead.org, netdev@vger.kernel.org, Russell King , "David S. Miller" To: Ben Hutchings Return-path: Received: from mail.vipri.net ([89.207.250.2]:46771 "EHLO mail.vipri.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752224Ab1IBOAM (ORCPT ); Fri, 2 Sep 2011 10:00:12 -0400 Content-Disposition: inline In-Reply-To: <1314971179.3092.159.camel@deadeye> Sender: netdev-owner@vger.kernel.org List-ID: On Fri, Sep 02, 2011 at 02:46:17PM +0100, Ben Hutchings wrote: > On Fri, 2011-09-02 at 13:08 +0200, Phil Sutter wrote: > > This flushes the cache before and after accessing the mmapped packe= t > > buffer. It seems like the call to flush_dcache_page from inside > > __packet_get_status is not enough on Kirkwood (or ARM in general). > > --- > > I know this is far from an optimal solution, but it's in fact the o= nly working > > one I found. > [...] >=20 > This is ridiculous. If flush_dcache_page() isn't doing everything it > should, you need to fix that. You're absolutely correct. But in fact this problem goes way too deep for me to find it's cause. And since my time is finite, I doubt this will change in the near future. So I asked for help, a pointer in whatever direction or anything I could try to help further analyzing - without any response (unless I missed it, in which case I apologize). Please don't get me wrong. I have no intend in this patch becoming mainline, just want to give others with the same problem a starting point. Greetings, Phil --=20 Viprinet GmbH Mainzer Str. 43 55411 Bingen am Rhein Germany Zentrale: +49-6721-49030-0 Durchwahl: +49-6721-49030-134 =46ax: +49-6721-49030-209 phil.sutter@viprinet.com http://www.viprinet.com Sitz der Gesellschaft: Bingen am Rhein Handelsregister: Amtsgericht Mainz HRB40380 Gesch=C3=A4ftsf=C3=BChrer: Simon Kissel