Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751503AbZJWHYy (ORCPT ); Fri, 23 Oct 2009 03:24:54 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751313AbZJWHYx (ORCPT ); Fri, 23 Oct 2009 03:24:53 -0400 Received: from fmmailgate01.web.de ([217.72.192.221]:50925 "EHLO fmmailgate01.web.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751312AbZJWHYw (ORCPT ); Fri, 23 Oct 2009 03:24:52 -0400 From: Thomas Schlichter To: Suresh Siddha Subject: Re: [RFC Patch] use MTRR for write combining if PAT is not available Date: Fri, 23 Oct 2009 09:24:54 +0200 User-Agent: KMail/1.12.2 (Linux/2.6.28.10-bigboss; KDE/4.3.2; i686; ; ) Cc: Jesse Barnes , Eric Anholt , Thomas Hellstrom , Jeremy Fitzhardinge , "H. Peter Anvin" , Arjan van de Ven , "x86@kernel.org" , "linux-kernel@vger.kernel.org" , Jan Beulich , Ingo Molnar , Thomas Gleixner , Henrique de Moraes Holschuh , "Pallipadi, Venkatesh" , Tejun Heo , "dri-devel@lists.sourceforge.net" , Yinghai Lu , Ingo Molnar , Robert Hancock References: <1394846127@web.de> <20091023133152.1a15ba69@jbarnes-x200> <1256273896.2569.10.camel@sbs-t61> In-Reply-To: <1256273896.2569.10.camel@sbs-t61> MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-15" Content-Transfer-Encoding: 7bit Message-Id: <200910230924.54655.thomas.schlichter@web.de> X-Provags-ID: V01U2FsdGVkX1/woOD1QHdQCJRkRNYyzWRS+JTqBXraOS36fpih SwDThVUEqrn4vkWU+ZdcgFUUh5wuWAVZWvWCnPaXjYdpI+DGCe Lu+/33A4reooh/s+mEaw== Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1088 Lines: 30 Suresh Siddha wrote: > On Thu, 2009-10-22 at 21:31 -0700, Jesse Barnes wrote: > > Here's a quick & dirty version, totally untested. A cleaner approach > > would be to separate the WC mapping routines and hide the return > > -EINVAL in arch specific code... > > Jesse How about this patch? Doing this in x86 is cleaner. > > I would like Acks/sign-offs-by Thomas, Eric and Jesse, if it is ok with > this patch and works. Hmm, at this point I already was more than a week ago: http://marc.info/?l=linux-kernel&m=125537770514713&w=2 OK, I also modified ioremap() and set_memory_wc() but your patch is just part of what I did there... And Eric Anholt answered: > Seems like we should install an MTRR instead. Requiring userland to set > up the MTRR on the kernel's behalf is backwards. Where I totally agree with him. Regards, Thomas -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/