Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754021AbYKDKXV (ORCPT ); Tue, 4 Nov 2008 05:23:21 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753000AbYKDKXL (ORCPT ); Tue, 4 Nov 2008 05:23:11 -0500 Received: from mx3.mail.elte.hu ([157.181.1.138]:47203 "EHLO mx3.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752924AbYKDKXJ (ORCPT ); Tue, 4 Nov 2008 05:23:09 -0500 Date: Tue, 4 Nov 2008 11:22:52 +0100 From: Ingo Molnar To: Sam Ravnborg Cc: Andrew Morton , Rakib Mullick , linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org Subject: Re: [PATCH] kernel/cpu.c: Section mismatch warning fix. Message-ID: <20081104102252.GA14339@elte.hu> References: <20081103153425.7282ab84.akpm@linux-foundation.org> <20081104094831.GP23790@elte.hu> <20081104100912.GB6651@uranus.ravnborg.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20081104100912.GB6651@uranus.ravnborg.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,DNS_FROM_SECURITYSAGE autolearn=no SpamAssassin version=3.2.3 -1.5 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] 0.0 DNS_FROM_SECURITYSAGE RBL: Envelope sender in blackholes.securitysage.com Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4495 Lines: 120 * Sam Ravnborg wrote: > On Tue, Nov 04, 2008 at 10:48:31AM +0100, Ingo Molnar wrote: > > > > * Andrew Morton wrote: > > > > > On Thu, 30 Oct 2008 10:04:54 +0600 > > > "Rakib Mullick" wrote: > > > > > > > LD kernel/built-in.o > > > > WARNING: kernel/built-in.o(.text+0xb7c8): Section mismatch in > > > > reference from the function notify_cpu_starting() to the variable > > > > .cpuinit.data:cpu_chain > > > > The function notify_cpu_starting() references > > > > the variable __cpuinitdata cpu_chain. > > > > This is often because notify_cpu_starting lacks a __cpuinitdata > > > > annotation or the annotation of cpu_chain is wrong. > > > > > > > > This patch fixes the above section mismatch warning. If anything else > > > > please notice. > > > > Thanks. > > > > > > > > Signed-off-by: Md.Rakib H. Mullick > > > > > > > > --- linux-2.6-orig/kernel/cpu.c 2008-10-28 20:52:38.000000000 +0600 > > > > +++ linux-2.6/kernel/cpu.c 2008-10-28 22:46:22.000000000 +0600 > > > > @@ -462,7 +462,7 @@ out: > > > > * It must be called by the arch code on the new cpu, before the new cpu > > > > * enables interrupts and before the "boot" cpu returns from __cpu_up(). > > > > */ > > > > -void notify_cpu_starting(unsigned int cpu) > > > > +void __cpuinit notify_cpu_starting(unsigned int cpu) > > > > { > > > > unsigned long val = CPU_STARTING; > > > > > > arch/alpha/kernel/smp.c calls notify_cpu_starting() from __init code. > > > > > > arch/cris/arch-v32/kernel/smp.c calls notify_cpu_starting() from __init code. > > > > > > arch/x86/mach-voyager/voyager_smp.c calls notify_cpu_starting() from > > > __init code. > > > > > > arch/m32r/kernel/smpboot.c calls notify_cpu_starting() from __init code. > > > > > > arch/sparc/kernel/sun4d_smp.c calls notify_cpu_starting() from __init code. > > > > > > arch/powerpc/kernel/smp.c calls notify_cpu_starting() from __devinit > > > code. > > > > > > arch/um/kernel/smp.c calls notify_cpu_starting() from .text code. > > > > > > > > > The other nine callers call notify_cpu_starting() from __cpuinit code. > > > > > > > > > What a mess. > > > > __cpuinit seems safe for all but UML. > > > > But even for UML it appears to be de-facto safe: as after bootup we > > never return back into arch/um/kernel/smp.c::idle_proc(). (as UML's > >From the list Andrew provided powerpc needs to be looked after. > We cannot call an __init function from __devinit context. > If you already checked that then no objections. the patch/context in question is attached below - in that we weaken the persistency of notify_cpu_starting() from .text to __cpuinit. Which should be safe, right? Ingo --------> >From 685aebb5fb26126e9be708cfed30e5ee20033c95 Mon Sep 17 00:00:00 2001 From: Rakib Mullick Date: Thu, 30 Oct 2008 10:04:54 +0600 Subject: [PATCH] kernel/cpu.c: section mismatch warning fix Impact: small kernel .text reduction in certain configs, and fix warning This warning: LD kernel/built-in.o WARNING: kernel/built-in.o(.text+0xb7c8): Section mismatch in reference from the function notify_cpu_starting() to the variable .cpuinit.data:cpu_chain The function notify_cpu_starting() references the variable __cpuinitdata cpu_chain. This is often because notify_cpu_starting lacks a __cpuinitdata annotation or the annotation of cpu_chain is wrong. Points out the fact that notify_cpu_starting() is only called from __cpuinit sequences and itself uses a __cpuinitdata structure. This patch fixes the above section mismatch warning. Signed-off-by: Md.Rakib H. Mullick Signed-off-by: Ingo Molnar --- kernel/cpu.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/kernel/cpu.c b/kernel/cpu.c index 86d4904..2e53420 100644 --- a/kernel/cpu.c +++ b/kernel/cpu.c @@ -462,7 +462,7 @@ out: * It must be called by the arch code on the new cpu, before the new cpu * enables interrupts and before the "boot" cpu returns from __cpu_up(). */ -void notify_cpu_starting(unsigned int cpu) +void __cpuinit notify_cpu_starting(unsigned int cpu) { unsigned long val = CPU_STARTING; -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/