From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:33683) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1b0qY0-0003RI-TZ for qemu-devel@nongnu.org; Thu, 12 May 2016 09:21:06 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1b0qXv-00013r-Rw for qemu-devel@nongnu.org; Thu, 12 May 2016 09:20:59 -0400 Received: from mx1.redhat.com ([209.132.183.28]:42823) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1b0qXv-00013n-Mg for qemu-devel@nongnu.org; Thu, 12 May 2016 09:20:55 -0400 Received: from int-mx09.intmail.prod.int.phx2.redhat.com (int-mx09.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 04865C02C6B9 for ; Thu, 12 May 2016 13:20:55 +0000 (UTC) Date: Thu, 12 May 2016 15:20:51 +0200 From: Igor Mammedov Message-ID: <20160512152051.5d938f2a@nial.brq.redhat.com> In-Reply-To: <20160512110423.GE1946264@andariel.pipo.sk> References: <1462192431-146342-1-git-send-email-imammedo@redhat.com> <1462192431-146342-13-git-send-email-imammedo@redhat.com> <20160510202414.GD4457@thinpad.lan.raisama.net> <20160511155039.320c3de6@nial.brq.redhat.com> <20160512005017-mutt-send-email-mst@redhat.com> <20160511232859.GI4457@thinpad.lan.raisama.net> <20160512100606-mutt-send-email-mst@redhat.com> <20160512122955.006159de@nial.brq.redhat.com> <20160512105223.GK4457@thinpad.lan.raisama.net> <20160512110423.GE1946264@andariel.pipo.sk> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [libvirt] [RFC 12/42] pc: initialize legacy hotplug only for 2.6 and older machine types List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Peter Krempa Cc: Eduardo Habkost , drjones@redhat.com, "Michael S. Tsirkin" , libvir-list@redhat.com, qemu-devel@nongnu.org, marcel@redhat.com On Thu, 12 May 2016 13:04:23 +0200 Peter Krempa wrote: > On Thu, May 12, 2016 at 07:52:23 -0300, Eduardo Habkost wrote: > > I don't think we should do that, unless users already had time to > > update their scripts and libvirt had time to implement code > > supporting the new method. > > > > I believe libvirt (and people's scripts) use maxcpus only when > > they want CPU hotplug, so making max_cpus > smp_cpus enable CPU > > hotplug implicitly would probably solve the compatibility issue. > > Libvirt uses maxcpus only if the configuration explicitly has less > active cpus than the maximum number. This option would be the best IMO. > > > If we want to deprecate the use of maxcpus to enable CPU hotplug, > > then we can make it print a warning for a few releases, so people > > have time to update their code. > > At that point libvirt also needs a way to detect that the new argument > is supported by qemu, so we can start passing it on the command line > basically every time we now pass 'maxcpus'. > > The warning will get most probably ignored by people using libvirt as > the stdout/err of qemu is not visible to them. Ok, to make things less complicated I'll drop machine.cpu-hotplug and leave it always enabled as it used to be and as Michael suggested. I'll drop following patches: 12, 13, 14, 20, 23 and respin series > > Peter