From mboxrd@z Thu Jan 1 00:00:00 1970 From: Glauber Costa Subject: Re: [PATCH] Set bit 1 in disabled processor's _STA Date: Mon, 18 May 2009 09:59:06 -0300 Message-ID: <20090518125906.GT27295@poweredge.glommer> References: <20090517150727.GO27295@poweredge.glommer> <20090517153022.GB21386@redhat.com> <4A106E83.6080302@redhat.com> <20090518051718.GL3909@redhat.com> <4A10F5D6.5060700@redhat.com> <20090518055358.GA6438@redhat.com> <20090518113943.GR27295@poweredge.glommer> <20090518114018.GB14536@redhat.com> <20090518124003.GS27295@poweredge.glommer> <20090518124210.GF14536@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Avi Kivity , kvm@vger.kernel.org To: Gleb Natapov Return-path: Received: from mx2.redhat.com ([66.187.237.31]:55563 "EHLO mx2.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750978AbZERMyA (ORCPT ); Mon, 18 May 2009 08:54:00 -0400 Received: from int-mx2.corp.redhat.com (int-mx2.corp.redhat.com [172.16.27.26]) by mx2.redhat.com (8.13.8/8.13.8) with ESMTP id n4ICs2r1000884 for ; Mon, 18 May 2009 08:54:02 -0400 Content-Disposition: inline In-Reply-To: <20090518124210.GF14536@redhat.com> Sender: kvm-owner@vger.kernel.org List-ID: On Mon, May 18, 2009 at 03:42:10PM +0300, Gleb Natapov wrote: > On Mon, May 18, 2009 at 09:40:03AM -0300, Glauber Costa wrote: > > On Mon, May 18, 2009 at 02:40:18PM +0300, Gleb Natapov wrote: > > > On Mon, May 18, 2009 at 08:39:43AM -0300, Glauber Costa wrote: > > > > > Now I recall something on LKML about this. Well, in this case Linux > > > > > shouldn't have used ACPI to invent its own way to do cpu hot-plug. > > > > It didn't. > > > > History shows that this method is what is used in some unisys machines, > > > > which seems to be the only ones implementing this around. > > > The questions are: What is "this" that linux currently implements, how > > > windows expects CPU hot-plug to work, are there any real x86 hardware > > > that supports CPU host-plug and what should we do about all this. > > as I said, there are unisys machines that implements cpu hotplug. > > The way they do it, is the way Linux kernel currently expects. The same way > > we implement on our BIOS. > I read that document too. And "based on some input from Natalie of Unisys" > does not sound promising. I'm not saying it is promising. Nothing un-specified is. Google search for the mails exchanged on the time of development of this also point in the direction that this is probably all we have. > Are those Unisys machines certified to run > Windows 2008? Because if they are, they surely do something different > from what we are doing. Unless they have a time machine, it is unlikely. Windows 2008 did not exist at the time