Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751439AbZJWBx2 (ORCPT ); Thu, 22 Oct 2009 21:53:28 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751289AbZJWBx1 (ORCPT ); Thu, 22 Oct 2009 21:53:27 -0400 Received: from 71-20-254-182.war.clearwire-wmx.net ([71.20.254.182]:35196 "EHLO kingsolver.anholt.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751265AbZJWBx0 (ORCPT ); Thu, 22 Oct 2009 21:53:26 -0400 Subject: Re: [RFC Patch] use MTRR for write combining if PAT is not available From: Eric Anholt To: Suresh Siddha Cc: Jesse Barnes , Thomas Schlichter , Ingo Molnar , Jan Beulich , Jeremy Fitzhardinge , Robert Hancock , Henrique de Moraes Holschuh , "Pallipadi, Venkatesh" , Tejun Heo , "x86@kernel.org" , Yinghai Lu , Thomas Gleixner , Arjan van de Ven , "dri-devel@lists.sourceforge.net" , Ingo Molnar , "linux-kernel@vger.kernel.org" , Thomas Hellstrom , "H. Peter Anvin" In-Reply-To: <1256256717.2534.6.camel@sbs-t61> References: <1394846127@web.de> <4ADF32A0020000780001B20A@vpn.id2.novell.com> <20091021173514.GA32227@elte.hu> <200910212201.36578.thomas.schlichter@web.de> <1256205210.2530.28.camel@sbs-t61> <1256225689.32075.6.camel@gaiman.anholt.net> <1256248050.2546.9.camel@sbs-t61> <20091023081047.4d8abc29@jbarnes-x200> <1256256717.2534.6.camel@sbs-t61> Content-Type: multipart/signed; micalg="pgp-sha1"; protocol="application/pgp-signature"; boundary="=-uTzHHxb5+7CDQs6cf6Dn" Date: Thu, 22 Oct 2009 18:53:19 -0700 Message-Id: <1256262799.15120.8.camel@gaiman.anholt.net> Mime-Version: 1.0 X-Mailer: Evolution 2.28.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1879 Lines: 55 --=-uTzHHxb5+7CDQs6cf6Dn Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Thu, 2009-10-22 at 17:11 -0700, Suresh Siddha wrote: > On Thu, 2009-10-22 at 16:10 -0700, Jesse Barnes wrote: > > On Thu, 22 Oct 2009 14:47:30 -0700 > > Suresh Siddha wrote: > >=20 > > > On Thu, 2009-10-22 at 08:34 -0700, Eric Anholt wrote: > > > > Can we just not create the _wc sysfs entry if we don't have PAT? I > > > > don't think there's userland relying on its presence as opposed to > > > > the non-_wc entry. > > >=20 > > > Yes indeed. Jesse do you see an issue with this? This is simple and > > > clean. Thanks Eric. > >=20 > > Yeah, I think that will be fine. In fact, older versions of > > libpciaccess will behave better if we do it that way (iirc it only > > allocates an MTRR if the resource_wc file doesn't exist or fails to get > > mapped). >=20 > Eric, care to send the patch? I don't have a patch, I was just suggesting a way to handle the submitter's problem that won't involve complicated changes that nobody else will be testing since everyone *should* have a graphics driver for their graphics hardware. --=20 Eric Anholt eric@anholt.net eric.anholt@intel.com --=-uTzHHxb5+7CDQs6cf6Dn Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.10 (GNU/Linux) iEYEABECAAYFAkrhDI8ACgkQHUdvYGzw6vfDewCfaqYR5TjG0zpwoH4xd+zJ2FlO 6SEAn2ES4srqXKhLObGI8ROujoiHxAba =1JuF -----END PGP SIGNATURE----- --=-uTzHHxb5+7CDQs6cf6Dn-- -- 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/