From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751965Ab2GZJim (ORCPT ); Thu, 26 Jul 2012 05:38:42 -0400 Received: from mail4.hitachi.co.jp ([133.145.228.5]:52181 "EHLO mail4.hitachi.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750766Ab2GZJik (ORCPT ); Thu, 26 Jul 2012 05:38:40 -0400 X-AuditID: b753bd60-a0885ba000000655-b9-5011101ed996 X-AuditID: b753bd60-a0885ba000000655-b9-5011101ed996 Message-ID: <50111029.6040408@hitachi.com> Date: Thu, 26 Jul 2012 18:38:49 +0900 From: Tomoki Sekiyama User-Agent: Mozilla/5.0 (Windows NT 5.1; rv:12.0) Gecko/20120428 Thunderbird/12.0.1 MIME-Version: 1.0 To: suresh.b.siddha@intel.com Cc: tglx@linutronix.de, mingo@kernel.org, hpa@zytor.com, yinghai@kernel.org, agordeev@redhat.com, x86@kernel.org, linux-kernel@vger.kernel.org, yrl.pp-manager.tt@hitachi.com Subject: Re: [PATCH] x86/ioapic: Fix NULL pointer dereference on CPU hotplug after disabling irqs References: <500FB9C2.1030103@hitachi.com> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit X-Brightmail-Tracker: AAAAAA== Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, thanks for your comment. On 2012/07/26 8:28, Siddha, Suresh B wrote: > Tomoki wrote: >> In current Linux, percpu variable `vector_irq' is not always cleared when >> a CPU is offlined. If the cpu that has the disabled irqs in vector_irq is >> hotplugged again, __setup_vector_irq() hits invalid irq vector and may >> crash. >> >> Commit f6175f5bfb4c partially fixes this, but was not enough in >> environments with IOMMU IRQ remapper. > > So, this patch essentially makes the commit f6175f5bfb4c unnecessary, right? > > Can you revert that too as part of this new proposed patch? > > thanks, > suresh OK, I will include a reverse patch of f6175f5bfb4c and resend the patch. Thanks, -- Tomoki Sekiyama Linux Technology Center Hitachi, Ltd., Yokohama Research Laboratory