From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757274Ab2HOUdW (ORCPT ); Wed, 15 Aug 2012 16:33:22 -0400 Received: from mail1.windriver.com ([147.11.146.13]:62785 "EHLO mail1.windriver.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756365Ab2HOTtf (ORCPT ); Wed, 15 Aug 2012 15:49:35 -0400 From: Paul Gortmaker To: , CC: Konrad Rzeszutek Wilk , Paul Gortmaker Subject: [v2.6.34-stable 033/165] xen/smp: Warn user why they keel over - nosmp or noapic and what to use instead. Date: Wed, 15 Aug 2012 15:46:17 -0400 Message-ID: <1345060109-9187-34-git-send-email-paul.gortmaker@windriver.com> X-Mailer: git-send-email 1.7.12.rc2 In-Reply-To: <1345060109-9187-1-git-send-email-paul.gortmaker@windriver.com> References: <1345060109-9187-1-git-send-email-paul.gortmaker@windriver.com> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Konrad Rzeszutek Wilk ------------------- This is a commit scheduled for the next v2.6.34 longterm release. http://git.kernel.org/?p=linux/kernel/git/paulg/longterm-queue-2.6.34.git If you see a problem with using this for longterm, please comment. ------------------- commit ed467e69f16e6b480e2face7bc5963834d025f91 upstream. We have hit a couple of customer bugs where they would like to use those parameters to run an UP kernel - but both of those options turn of important sources of interrupt information so we end up not being able to boot. The correct way is to pass in 'dom0_max_vcpus=1' on the Xen hypervisor line and the kernel will patch itself to be a UP kernel. Fixes bug: http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=637308 Acked-by: Ian Campbell Signed-off-by: Konrad Rzeszutek Wilk Signed-off-by: Paul Gortmaker --- arch/x86/xen/smp.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/arch/x86/xen/smp.c b/arch/x86/xen/smp.c index d2dfbf5..9aac865 100644 --- a/arch/x86/xen/smp.c +++ b/arch/x86/xen/smp.c @@ -31,6 +31,7 @@ #include #include +#include #include "xen-ops.h" #include "mmu.h" @@ -181,6 +182,15 @@ static void __init xen_smp_prepare_cpus(unsigned int max_cpus) { unsigned cpu; + if (skip_ioapic_setup) { + char *m = (max_cpus == 0) ? + "The nosmp parameter is incompatible with Xen; " \ + "use Xen dom0_max_vcpus=1 parameter" : + "The noapic parameter is incompatible with Xen"; + + xen_raw_printk(m); + panic(m); + } xen_init_lock_cpu(0); smp_store_cpu_info(0); -- 1.7.12.rc2