From patchwork Thu Nov 2 10:10:06 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Thomas Huth X-Patchwork-Id: 10038275 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id EBD05603D7 for ; Thu, 2 Nov 2017 10:11:26 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id DA93228EDE for ; Thu, 2 Nov 2017 10:11:26 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id CF53F28EE1; Thu, 2 Nov 2017 10:11:26 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 66B9F28EE0 for ; Thu, 2 Nov 2017 10:11:26 +0000 (UTC) Received: from localhost ([::1]:59480 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eACT7-0000R0-Ia for patchwork-qemu-devel@patchwork.kernel.org; Thu, 02 Nov 2017 06:11:25 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:41550) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eACS4-0000Pa-Gd for qemu-devel@nongnu.org; Thu, 02 Nov 2017 06:10:21 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1eACS2-0002hO-NY for qemu-devel@nongnu.org; Thu, 02 Nov 2017 06:10:20 -0400 Received: from mx1.redhat.com ([209.132.183.28]:36758) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1eACS2-0002gI-2C for qemu-devel@nongnu.org; Thu, 02 Nov 2017 06:10:18 -0400 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 389105D686 for ; Thu, 2 Nov 2017 10:10:17 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 389105D686 Authentication-Results: ext-mx10.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx10.extmail.prod.ext.phx2.redhat.com; spf=fail smtp.mailfrom=thuth@redhat.com Received: from thh440s.redhat.com (ovpn-116-111.ams2.redhat.com [10.36.116.111]) by smtp.corp.redhat.com (Postfix) with ESMTP id 3A14F600C0; Thu, 2 Nov 2017 10:10:15 +0000 (UTC) From: Thomas Huth To: qemu-devel@nongnu.org, Eduardo Habkost , Igor Mammedov , "Dr. David Alan Gilbert" Date: Thu, 2 Nov 2017 11:10:06 +0100 Message-Id: <1509617407-21191-3-git-send-email-thuth@redhat.com> In-Reply-To: <1509617407-21191-1-git-send-email-thuth@redhat.com> References: <1509617407-21191-1-git-send-email-thuth@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.39]); Thu, 02 Nov 2017 10:10:17 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PATCH v3 2/2] qdev: Check for the availability of a hotplug controller before adding a device X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Paolo Bonzini , Markus Armbruster , david@redhat.com Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" X-Virus-Scanned: ClamAV using ClamSMTP The qdev_unplug() function contains a g_assert(hotplug_ctrl) statement, so QEMU crashes when the user tries to device_add + device_del a device that does not have a corresponding hotplug controller. This could be provoked for a couple of devices in the past (see commit 4c93950659487c7ad or 84ebd3e8c7d4fe955 for example), and can currently for example also be triggered like this: $ s390x-softmmu/qemu-system-s390x -M none -nographic QEMU 2.10.50 monitor - type 'help' for more information (qemu) device_add qemu-s390x-cpu,id=x (qemu) device_del x ** ERROR:qemu/qdev-monitor.c:872:qdev_unplug: assertion failed: (hotplug_ctrl) Aborted (core dumped) So devices clearly need a hotplug controller when they should be usable with device_add. The code in qdev_device_add() already checks whether the bus has a proper hotplug controller, but for devices that do not have a corresponding bus, there is no appropriate check available yet. In that case we should check whether the machine itself provides a suitable hotplug controller and refuse to plug the device if none is available. Reviewed-by: Igor Mammedov Signed-off-by: Thomas Huth Reviewed-by: Cornelia Huck --- hw/core/qdev.c | 28 ++++++++++++++++++++-------- include/hw/qdev-core.h | 1 + qdev-monitor.c | 5 +++++ 3 files changed, 26 insertions(+), 8 deletions(-) diff --git a/hw/core/qdev.c b/hw/core/qdev.c index 1111295..f739753 100644 --- a/hw/core/qdev.c +++ b/hw/core/qdev.c @@ -253,19 +253,31 @@ void qdev_set_legacy_instance_id(DeviceState *dev, int alias_id, dev->alias_required_for_version = required_for_version; } +HotplugHandler *qdev_get_machine_hotplug_handler(DeviceState *dev) +{ + MachineState *machine; + MachineClass *mc; + Object *m_obj = qdev_get_machine(); + + if (object_dynamic_cast(m_obj, TYPE_MACHINE)) { + machine = MACHINE(m_obj); + mc = MACHINE_GET_CLASS(machine); + if (mc->get_hotplug_handler) { + return mc->get_hotplug_handler(machine, dev); + } + } + + return NULL; +} + HotplugHandler *qdev_get_hotplug_handler(DeviceState *dev) { - HotplugHandler *hotplug_ctrl = NULL; + HotplugHandler *hotplug_ctrl; if (dev->parent_bus && dev->parent_bus->hotplug_handler) { hotplug_ctrl = dev->parent_bus->hotplug_handler; - } else if (object_dynamic_cast(qdev_get_machine(), TYPE_MACHINE)) { - MachineState *machine = MACHINE(qdev_get_machine()); - MachineClass *mc = MACHINE_GET_CLASS(machine); - - if (mc->get_hotplug_handler) { - hotplug_ctrl = mc->get_hotplug_handler(machine, dev); - } + } else { + hotplug_ctrl = qdev_get_machine_hotplug_handler(dev); } return hotplug_ctrl; } diff --git a/include/hw/qdev-core.h b/include/hw/qdev-core.h index 0a71bf8..51473ee 100644 --- a/include/hw/qdev-core.h +++ b/include/hw/qdev-core.h @@ -286,6 +286,7 @@ DeviceState *qdev_try_create(BusState *bus, const char *name); void qdev_init_nofail(DeviceState *dev); void qdev_set_legacy_instance_id(DeviceState *dev, int alias_id, int required_for_version); +HotplugHandler *qdev_get_machine_hotplug_handler(DeviceState *dev); HotplugHandler *qdev_get_hotplug_handler(DeviceState *dev); void qdev_unplug(DeviceState *dev, Error **errp); void qdev_simple_device_unplug_cb(HotplugHandler *hotplug_dev, diff --git a/qdev-monitor.c b/qdev-monitor.c index 9188d20..38c0fc2 100644 --- a/qdev-monitor.c +++ b/qdev-monitor.c @@ -614,6 +614,11 @@ DeviceState *qdev_device_add(QemuOpts *opts, Error **errp) if (bus) { qdev_set_parent_bus(dev, bus); + } else if (qdev_hotplug && !qdev_get_machine_hotplug_handler(dev)) { + /* No bus, no machine hotplug handler --> device is not hotpluggable */ + error_setg(&err, "Device '%s' can not be hotplugged on this machine", + driver); + goto err_del_dev; } qdev_set_id(dev, qemu_opts_id(opts));