From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754783AbYICE46 (ORCPT ); Wed, 3 Sep 2008 00:56:58 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751272AbYICE4t (ORCPT ); Wed, 3 Sep 2008 00:56:49 -0400 Received: from rv-out-0506.google.com ([209.85.198.230]:19317 "EHLO rv-out-0506.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751069AbYICE4s (ORCPT ); Wed, 3 Sep 2008 00:56:48 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:to:subject:cc:in-reply-to:mime-version :content-type:content-transfer-encoding:content-disposition :references; b=jMtVJJjlR5P9O8PkPf3b2i/FCtNvIR4WPv0bUZTfOTH8KkLNPjrvcVNq63du2P7s4y KiSyqRrJhEa1dsESo4o/1Gh2+ZYmTnZ03qMcdeGzNrDxWRRaRodVGhbo8z5yzj3ID9Yo lKlBsXFvSWfmUKuvSn769FyxQQ+ImCX4dfDm8= Message-ID: <86802c440809022156t598ee53fvdd2ae60626737b23@mail.gmail.com> Date: Tue, 2 Sep 2008 21:56:47 -0700 From: "Yinghai Lu" To: "Bob Tracy" Subject: Re: [BUG] /proc/mtrr I/O error Cc: "Andrew Morton" , linux-kernel@vger.kernel.org In-Reply-To: <20080903035821.GA2293@gherkin.frus.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <20080829213824.GA2281@gherkin.frus.com> <20080902154620.314ad5c2.akpm@linux-foundation.org> <86802c440809021608s54725294t5629255bb1f0c9@mail.gmail.com> <20080903035821.GA2293@gherkin.frus.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Sep 2, 2008 at 8:58 PM, Bob Tracy wrote: > On Tue, Sep 02, 2008 at 04:08:00PM -0700, Yinghai Lu wrote: >> On Tue, Sep 2, 2008 at 3:46 PM, Andrew Morton wrote: >> > On Fri, 29 Aug 2008 16:38:24 -0500 >> > Bob Tracy wrote: >> > >> >> With 2.6.27-rc4 and possibly earlier kernels, I see the following: >> >> >> >> $ cat /proc/mtrr >> >> cat: /proc/mtrr: Input/output error >> >> >> >> Processor is an AMD K6-III/450. >> >> >> > >> > static int mtrr_open(struct inode *inode, struct file *file) >> > { >> > if (!mtrr_if) >> > return -EIO; >> > >> > >> > >> > Beats me. Perhaps something broke in mtrr_bp_init(). >> > >> > It would be useful to know if 2.6.26 worked OK. >> > >> >> two patches needed.. >> >> http://lkml.org/lkml/2008/9/1/307 >> [PATCH 4/6] x86: delay early cpu initialization until cpuid is done >> http://lkml.org/lkml/2008/9/1/308 >> [PATCH 5/6] x86: move mtrr cpu cap setting early in early_init_xxxx > > Krzysztof Helt's quick-and-dirty patch posted a few days ago did the > trick, but from the descriptions of the above patches, they address the > problem properly. Here's what "cat /proc/mtrr" shows with Helt's patch > and the "nv" driver active for my GeForce2 MX 400 card: > > $ cat /proc/mtrr > reg00: base=0xd0000000 (3328MB), size= 64MB: write-combining, count=1 > > MTRR sanitization seems to be working properly: the same command shows > nothing when X isn't running. did you apply them both [PATCH 4/6] x86: delay early cpu initialization until cpuid is done [PATCH 5/6] x86: move mtrr cpu cap setting early in early_init_xxxx YH