From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Hildenbrand Subject: Re: [PATCH v2 0/3] KVM: x86: use pic/ioapic destructor when proper Date: Wed, 15 Mar 2017 12:15:24 +0100 Message-ID: <2cb28e66-b24a-efba-92d1-55ffd39743c6@redhat.com> References: <1489564879-6097-1-git-send-email-peterx@redhat.com> <20170315085936.GD5971@pxdev.xzpeter.org> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Cc: kvm@vger.kernel.org, Paolo Bonzini , =?UTF-8?B?UmFkaW0gS3LEjW3DocWZ?= To: Peter Xu Return-path: Received: from mx1.redhat.com ([209.132.183.28]:40914 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752861AbdCOLP1 (ORCPT ); Wed, 15 Mar 2017 07:15:27 -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 8B5D064F4 for ; Wed, 15 Mar 2017 11:15:27 +0000 (UTC) In-Reply-To: <20170315085936.GD5971@pxdev.xzpeter.org> Sender: kvm-owner@vger.kernel.org List-ID: Am 15.03.2017 um 09:59 schrieb Peter Xu: > On Wed, Mar 15, 2017 at 09:47:14AM +0100, David Hildenbrand wrote: >> Am 15.03.2017 um 09:01 schrieb Peter Xu: >>> v2: >>> - add one more patch (patch 2 in v2) to check pic/ioapic's >>> existance before destroying them >> >> Patch 2+3 without 1 should work, too, right? > > We may need that? When destroy VM, it's: > > kvm_destroy_vm() > foreach (bus) do kvm_io_bus_destroy() > kfree(bus) <--- [1] > kvm_arch_destroy_vm() > kvm_pic_destroy() > kvm_io_bus_unregister_dev() <--- [2] > Wouldn't the natural way be 1. kvm_arch_destroy_vm() 2. foreach (bus) do kvm_io_bus_destroy() kfree(bus) Then we wouldn't have to deal with suddenly removed buses. But maybe that order is of importance here ... > Here if without patch 1 we'll reference bus->dev_count in [2], while > actually the bus has been freed already in [1]. Thanks, > > -- peterx > -- Thanks, David