From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753950AbYIHQ5H (ORCPT ); Mon, 8 Sep 2008 12:57:07 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752297AbYIHQ4z (ORCPT ); Mon, 8 Sep 2008 12:56:55 -0400 Received: from one.firstfloor.org ([213.235.205.2]:41922 "EHLO one.firstfloor.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752050AbYIHQ4z (ORCPT ); Mon, 8 Sep 2008 12:56:55 -0400 Date: Mon, 8 Sep 2008 19:00:29 +0200 From: Andi Kleen To: Linus Torvalds Cc: "H. Peter Anvin" , Andi Kleen , linux@sandersweb.net, linux-kernel@vger.kernel.org, the arch/x86 maintainers , Andi Kleen Subject: Re: [BUG] x86 kenel won't boot under Virtual PC Message-ID: <20080908170029.GP26079@one.firstfloor.org> References: <200809071922.32974.linux@sandersweb.net> <48C48467.40703@zytor.com> <200809072249.17280.linux@sandersweb.net> <48C4A46B.90705@zytor.com> <20080908154535.GL26079@one.firstfloor.org> <48C54839.8050304@zytor.com> <48C54F1B.8040604@zytor.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.4.2.1i Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Sep 08, 2008 at 09:20:06AM -0700, Linus Torvalds wrote: > > > On Mon, 8 Sep 2008, H. Peter Anvin wrote: > > > > And yes, it should be the default. The patch I have makes it > > "default y" as well as change the help text. > > It sounds like it shouldn't be a default at all, it should just _always_ > be on, if there really are gcc's that care that much. Most of our Originally it was an option because the 128 byte cache line it selects caused bloat in several important data structures. That was back then when cache line padded NR_CPUs arrays were still pretty common. I don't know if it's still a problem, but before making it default y it would be good to check the dynamic+static memory cost at least. -Andi