From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760638Ab0JGNqQ (ORCPT ); Thu, 7 Oct 2010 09:46:16 -0400 Received: from terminus.zytor.com ([198.137.202.10]:42555 "EHLO mail.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1760598Ab0JGNqP (ORCPT ); Thu, 7 Oct 2010 09:46:15 -0400 Message-ID: <4CADCF23.5070800@zytor.com> Date: Thu, 07 Oct 2010 06:46:11 -0700 From: "H. Peter Anvin" User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.2.9) Gecko/20100921 Fedora/3.1.4-1.fc13 Thunderbird/3.1.4 MIME-Version: 1.0 To: Jan Beulich CC: linux-kernel@vger.kernel.org Subject: Re: patch disabling use of PSE on Atom CPUs with a certain erratum References: <4CADAB3A020000780001B30A@vpn.id2.novell.com> In-Reply-To: <4CADAB3A020000780001B30A@vpn.id2.novell.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 10/07/2010 02:12 AM, Jan Beulich wrote: > In commit 7a0fc404ae663776e96db43879a0fa24fec1fa3a you > disable use of PSE, but I wonder how this can take any effect on > 64-bit CPUs, as they use large pages during early boot already. > Those pages, when use of PSE gets disabled, will get broken up > into 4k pages in phys_pmd_init(), thus actually increasing the > chances that you hit the erratum. > > What am I missing? > Those Atoms don't have 64-bit support. -hpa -- H. Peter Anvin, Intel Open Source Technology Center I work for Intel. I don't speak on their behalf.