From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:60049) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XWntw-0003Bv-NC for qemu-devel@nongnu.org; Wed, 24 Sep 2014 10:50:47 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1XWntq-0004qM-1d for qemu-devel@nongnu.org; Wed, 24 Sep 2014 10:50:40 -0400 Received: from mx1.redhat.com ([209.132.183.28]:38521) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XWntp-0004p3-TA for qemu-devel@nongnu.org; Wed, 24 Sep 2014 10:50:33 -0400 Message-ID: <5422DA29.9030806@redhat.com> Date: Wed, 24 Sep 2014 16:50:17 +0200 From: Paolo Bonzini MIME-Version: 1.0 References: <1411559299-19042-1-git-send-email-imammedo@redhat.com> <1411559299-19042-15-git-send-email-imammedo@redhat.com> <5422B775.90205@redhat.com> <20140924163748.18dbc40c@nial.usersys.redhat.com> In-Reply-To: <20140924163748.18dbc40c@nial.usersys.redhat.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH 14/30] target-i386: ICC bus: replace BusState.allow_hotplug with hotplug_handler List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Igor Mammedov Cc: dmitry@daynix.com, mst@redhat.com, agraf@suse.de, qemu-devel@nongnu.org, cornelia.huck@de.ibm.com, kraxel@redhat.com, amit.shah@redhat.com, borntraeger@de.ibm.com, rth@twiddle.net Il 24/09/2014 16:37, Igor Mammedov ha scritto: >> > If you do this, aren't you enabling CPU hot-unplug? Should >> > hotplug_handler_plug and/or hotplug_handler_unplug return an error if >> > there is no callback? > hotplug/unplug of x86 CPU is not usable with device_add/del yet, so > it's not used for CPUs yet. > x86 CPU nor APIC don't have DeviceClass.unplug callback so for old > behavior any attempt to call device_del would cause abort. > With this path attempt would become NOP. Can you make it an error instead? I guess that's related to the other question---whether hotplug_handler_plug and/or hotplug_handler_unplug should return an error if there is no callback. Paolo