From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753390AbbGaP1S (ORCPT ); Fri, 31 Jul 2015 11:27:18 -0400 Received: from mail.skyhub.de ([78.46.96.112]:48554 "EHLO mail.skyhub.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752792AbbGaP1P (ORCPT ); Fri, 31 Jul 2015 11:27:15 -0400 Date: Fri, 31 Jul 2015 17:27:13 +0200 From: Borislav Petkov To: Peter Zijlstra Cc: mingo@kernel.org, hpa@zytor.com, dvlasenk@redhat.com, bp@suse.de, akpm@linux-foundation.org, brgerst@gmail.com, tglx@linutronix.de, linux-mm@kvack.org, luto@amacapital.net, mcgrof@suse.com, toshi.kani@hp.com, torvalds@linux-foundation.org, linux-kernel@vger.kernel.org, linux-tip-commits@vger.kernel.org Subject: Re: [tip:x86/mm] x86/mm/mtrr: Clean up mtrr_type_lookup() Message-ID: <20150731152713.GA9756@nazgul.tnic> References: <1431714237-880-6-git-send-email-toshi.kani@hp.com> <1432628901-18044-6-git-send-email-bp@alien8.de> <20150731131802.GW25159@twins.programming.kicks-ass.net> <20150731144452.GA8106@nazgul.tnic> <20150731150806.GX25159@twins.programming.kicks-ass.net> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20150731150806.GX25159@twins.programming.kicks-ass.net> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jul 31, 2015 at 05:08:06PM +0200, Peter Zijlstra wrote: > But its things like set_memory_XX(), and afaict that's all buggy against > MTRR modifications. I think the idea is to not do any MTRR modifications at some point: >>From Documentation/x86/pat.txt: "... Ideally mtrr_add() usage will be phased out in favor of arch_phys_wc_add() which will be a no-op on PAT enabled systems. The region over which a arch_phys_wc_add() is made, should already have been ioremapped with WC attributes or PAT entries, this can be done by using ioremap_wc() / set_memory_wc()." -- Regards/Gruss, Boris. ECO tip #101: Trim your mails when you reply. --