From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ian Campbell Subject: Re: xen dependant on pcpu 0 ? Date: Tue, 12 Oct 2010 18:13:02 +0100 Message-ID: <1286903582.5663.167.camel@localhost.localdomain> References: <1452957126.20101012182813@eikelenboom.it> <20101012164433.GB21567@dumpdata.com> Mime-Version: 1.0 Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20101012164433.GB21567@dumpdata.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Konrad Rzeszutek Wilk Cc: Sander Eikelenboom , Jeremy Fitzhardinge , "xen-devel@lists.xensource.com" , Keir Fraser List-Id: xen-devel@lists.xenproject.org On Tue, 2010-10-12 at 17:44 +0100, Konrad Rzeszutek Wilk wrote: > On Tue, Oct 12, 2010 at 06:28:13PM +0200, Sander Eikelenboom wrote: > > Hi Keir, > > > > Does xen and/or the xen console depend on physical cpu 0 ? > > Usually the console for Dom0, and I think all other domains go > through CPU0. Let me CC Ian here, who has been mucking in this > area and found some bugs (and produced fixes). > > Ian, that bug you found with not clearing the eventchannel - that > wouldn't have an impact here, right? I don't think so. That issue was related to evtchn delivery which is to VCPUs not PCPUs. I don't think it was specific to VCPU0 either -- it just happened that the particular evtchn was generally tied to VCPU0 by default. I don't think the problem would happen for PIRQs anyway since the ->startup method for that IRQ chip includes an explicit rebind of the evtchn to a VCPU, it's only dynirqs which have the issue. Ian.