From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932429Ab1KDPgJ (ORCPT ); Fri, 4 Nov 2011 11:36:09 -0400 Received: from e7.ny.us.ibm.com ([32.97.182.137]:52847 "EHLO e7.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932185Ab1KDPgI (ORCPT ); Fri, 4 Nov 2011 11:36:08 -0400 Message-ID: <4EB403C0.3040803@austin.ibm.com> Date: Fri, 04 Nov 2011 10:24:48 -0500 From: Joel Schopp User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:7.0.1) Gecko/20110929 Thunderbird/7.0.1 MIME-Version: 1.0 To: hagar CC: lkml , Rusty Russell , Srivatsa Vaddagiri , Zwane Mwaikambo , Nathan Lynch , Ashok Raj , Heiko Carstens Subject: Re: Fwd: Kernel Power management ?? turning off used devices that are in use. References: <4EA67567.3020704@iinet.net.au> <4EB38A44.5030606@iinet.net.au> In-Reply-To: <4EB38A44.5030606@iinet.net.au> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit x-cbid: 11110415-5806-0000-0000-0000022E46B5 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > I need to be able to either switch off cpu hotpluging - or at least > prevent hotplugging certain cpu's > > there should really be a mincpu's option or better a > nohotplug="0,1,2,5,7,etc" option. > > It would appear that cpu1 is the default cpu for those interrupts - > and they are not being transferred to cpu0 properly. > The proper way to fix this is to find why the interrupts are not being transferred and fix that. Forcing cpus to not be hotpluggable is just hiding the problem. > I have tried the kernel parameters noapic nosmp maxcpus acpi=off > possible_cpus=2 etc - with no success > > I did find a flaw in "possible_cpus=0" - this prevents the kernel > booting (no cpus available ) > This option should be set to a minimum of 1 > We allow users to shoot themselves in the foot if they do silly things. This is a design decision.