From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756721AbYFBKLa (ORCPT ); Mon, 2 Jun 2008 06:11:30 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752111AbYFBKLW (ORCPT ); Mon, 2 Jun 2008 06:11:22 -0400 Received: from mx3.mail.elte.hu ([157.181.1.138]:49212 "EHLO mx3.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751593AbYFBKLV (ORCPT ); Mon, 2 Jun 2008 06:11:21 -0400 Date: Mon, 2 Jun 2008 12:10:59 +0200 From: Ingo Molnar To: Jeremy Fitzhardinge Cc: LKML , xen-devel , Thomas Gleixner , "Rafael J. Wysocki" , x86@kernel.org, Sam Ravnborg Subject: Re: [bisected] Re: [PATCH 05 of 12] xen: add p2m mfn_list_list Message-ID: <20080602101059.GB7459@elte.hu> References: <20080528122813.GA5502@elte.hu> <483D65E6.3020604@goop.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <483D65E6.3020604@goop.org> User-Agent: Mutt/1.5.18 (2008-05-17) X-ELTE-VirusStatus: clean X-ELTE-SpamScore: -1.5 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-1.5 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.2.3 -1.5 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Jeremy Fitzhardinge wrote: > Subject: make page-aligned data and bss less fragile > > Making a variable page-aligned by using > __attribute__((section(".data.page_aligned"))) is fragile because if > sizeof(variable) is not also a multiple of page size, it leaves > variables in the remainder of the section unaligned. > > This patch introduces two new qualifiers, __page_aligned_data and > __page_aligned_bss to set the section *and* the alignment of > variables. This makes page-aligned variables more robust because the > linker will make sure they're aligned properly. Unfortunately it > requires *all* page-aligned data to use these macros... applied to -tip, thanks Jeremy. Created a new topic branch for the core bits of it: tip/build. Sam might want to pull from that topic branch eventually, once these changes pass testing in -tip. Ingo