From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756173Ab3J1K5g (ORCPT ); Mon, 28 Oct 2013 06:57:36 -0400 Received: from mail.skyhub.de ([78.46.96.112]:50573 "EHLO mail.skyhub.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755409Ab3J1K5e (ORCPT ); Mon, 28 Oct 2013 06:57:34 -0400 Date: Mon, 28 Oct 2013 11:57:31 +0100 From: Borislav Petkov To: Andreas Werner Cc: Ingo Molnar , tglx@linutronix.de, mingo@redhat.com, hpa@zytor.com, x86@kernel.org, dave@linux.vnet.ibm.com, linux-kernel@vger.kernel.org Subject: Re: [PATCH] X86: MM: Add PAT Type write-through in combination with mtrr Message-ID: <20131028105731.GF4314@pd.tnic> References: <1382878525-3410-1-git-send-email-wernerandy@gmx.de> <20131027133401.GB24817@pd.tnic> <20131027165159.GD1617@thinkpad.fritz.box> <20131027173131.GC21868@pd.tnic> <20131027175608.GA1340@thinkpad.fritz.box> <20131027190148.GD21868@pd.tnic> <20131028062946.GA1391@thinkpad.fritz.box> <20131028101749.GA4389@gmail.com> <20131028103428.GA2278@thinkpad.fritz.box> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20131028103428.GA2278@thinkpad.fritz.box> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Oct 28, 2013 at 11:34:28AM +0100, Andreas Werner wrote: > Yes the reads are only for packet data, the commands or configuration > registers are mapped non cachable. > > I´ve tried WB, but on PCIe Tracer i could not see any burst access. > Thats the reason why i have created this patch. > > Is there a chance to get this patch into the kernel? Or > is this solution so special? Ok, but your patch returns WB pat type for WT MTRR type, AFAICT. You want to do: PAT=Write-Back + MTRR=Write-Through = Effective Memory of Write-Through but you end up doing PAT=Write-Back + MTRR=Write-Through = Effective Memory of Write-Back What am I missing or misunderstanding? AFAICT, you want to return _PAGE_PWT for MTRR_TYPE_WRTHROUGH, no? -- Regards/Gruss, Boris. Sent from a fat crate under my desk. Formatting is fine. --