From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754653AbaA1NWj (ORCPT ); Tue, 28 Jan 2014 08:22:39 -0500 Received: from mx1.redhat.com ([209.132.183.28]:2945 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750911AbaA1NWi (ORCPT ); Tue, 28 Jan 2014 08:22:38 -0500 From: Prarit Bhargava To: linux-kernel@vger.kernel.org Cc: Prarit Bhargava , Andi Kleen , Michel Lespinasse , Seiji Aguchi , Yang Zhang , Paul Gortmaker , Janet Morgan , Tony Luck , Ruiv Wang , Gong Chen , "H. Peter Anvin" , x86@kernel.org, Fengguang Wu , yinghai@kernel.org, tglx@linutronix.de, mingo@elte.hu, hpa@zytor.com Subject: [PATCH] x86, cpu hotplug, Fix stack frame warning in check_irq_vectors_for_cpu_disable() Date: Tue, 28 Jan 2014 08:22:11 -0500 Message-Id: <1390915331-27375-1-git-send-email-prarit@redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Further discussion here: http://marc.info/?l=linux-kernel&m=139073901101034&w=2 kbuild, 0day kernel build service, outputs the warning: arch/x86/kernel/irq.c:333:1: warning: the frame size of 2056 bytes is larger than 2048 bytes [-Wframe-larger-than=] because check_irq_vectors_for_cpu_disable() allocates two cpumasks on the stack. Fix this by moving the two cpumasks to a global file context. Signed-off-by: Prarit Bhargava Cc: Andi Kleen Cc: Michel Lespinasse Cc: Seiji Aguchi Cc: Yang Zhang Cc: Paul Gortmaker Cc: Janet Morgan Cc: Tony Luck Cc: Ruiv Wang Cc: Gong Chen Cc: H. Peter Anvin Cc: Gong Chen Cc: x86@kernel.org Cc: Fengguang Wu Cc: yinghai@kernel.org Cc: tglx@linutronix.de Cc: mingo@elte.hu Cc: hpa@zytor.com --- arch/x86/kernel/irq.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/arch/x86/kernel/irq.c b/arch/x86/kernel/irq.c index 4207e8d..3910078 100644 --- a/arch/x86/kernel/irq.c +++ b/arch/x86/kernel/irq.c @@ -262,6 +262,14 @@ __visible void smp_trace_x86_platform_ipi(struct pt_regs *regs) EXPORT_SYMBOL_GPL(vector_used_by_percpu_irq); #ifdef CONFIG_HOTPLUG_CPU + +/* These two declarations are only used in check_irq_vectors_for_cpu_disable() + * below, which is protected by stop_machine(). Putting them on the stack + * results in a stack frame overflow. Dynamically allocating could result in a + * failure so declare these two cpumasks as global. + */ +static struct cpumask affinity_new, online_new; + /* * This cpu is going to be removed and its vectors migrated to the remaining * online cpus. Check to see if there are enough vectors in the remaining cpus. @@ -273,7 +281,6 @@ int check_irq_vectors_for_cpu_disable(void) unsigned int this_cpu, vector, this_count, count; struct irq_desc *desc; struct irq_data *data; - struct cpumask affinity_new, online_new; this_cpu = smp_processor_id(); cpumask_copy(&online_new, cpu_online_mask); -- 1.7.9.3