Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935318AbcKNDBM (ORCPT ); Sun, 13 Nov 2016 22:01:12 -0500 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:47094 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933270AbcKNCXg (ORCPT ); Sun, 13 Nov 2016 21:23:36 -0500 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Thomas Gleixner" , "Peter Zijlstra" , "Wanpeng Li" , "Joerg Roedel" Date: Mon, 14 Nov 2016 00:14:07 +0000 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.2 084/152] x86/apic: Do not init irq remapping if ioapic is disabled In-Reply-To: X-SA-Exim-Connect-IP: 2a02:8011:400e:2:6f00:88c8:c921:d332 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1383 Lines: 44 3.2.84-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Wanpeng Li commit 2e63ad4bd5dd583871e6602f9d398b9322d358d9 upstream. native_smp_prepare_cpus -> default_setup_apic_routing -> enable_IR_x2apic -> irq_remapping_prepare -> intel_prepare_irq_remapping -> intel_setup_irq_remapping So IR table is setup even if "noapic" boot parameter is added. As a result we crash later when the interrupt affinity is set due to a half initialized remapping infrastructure. Prevent remap initialization when IOAPIC is disabled. Signed-off-by: Wanpeng Li Cc: Peter Zijlstra Cc: Joerg Roedel Link: http://lkml.kernel.org/r/1471954039-3942-1-git-send-email-wanpeng.li@hotmail.com Signed-off-by: Thomas Gleixner [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings --- arch/x86/kernel/apic/apic.c | 3 +++ 1 file changed, 3 insertions(+) --- a/arch/x86/kernel/apic/apic.c +++ b/arch/x86/kernel/apic/apic.c @@ -1481,6 +1481,9 @@ void __init enable_IR_x2apic(void) int ret, x2apic_enabled = 0; int dmar_table_init_ret; + if (skip_ioapic_setup) + return; + dmar_table_init_ret = dmar_table_init(); if (dmar_table_init_ret && !x2apic_supported()) return;