From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 3C827C433EF for ; Tue, 30 Nov 2021 12:32:20 +0000 (UTC) Received: from localhost ([::1]:56848 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1ms2J0-0004lt-SF for qemu-devel@archiver.kernel.org; Tue, 30 Nov 2021 07:32:18 -0500 Received: from eggs.gnu.org ([209.51.188.92]:38966) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1ms2HZ-0003wu-6E for qemu-devel@nongnu.org; Tue, 30 Nov 2021 07:30:49 -0500 Received: from mga09.intel.com ([134.134.136.24]:24857) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1ms2HW-000857-LT for qemu-devel@nongnu.org; Tue, 30 Nov 2021 07:30:48 -0500 X-IronPort-AV: E=McAfee;i="6200,9189,10183"; a="236028054" X-IronPort-AV: E=Sophos;i="5.87,275,1631602800"; d="scan'208";a="236028054" Received: from orsmga007.jf.intel.com ([10.7.209.58]) by orsmga102.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Nov 2021 04:30:24 -0800 X-IronPort-AV: E=Sophos;i="5.87,275,1631602800"; d="scan'208";a="499749988" Received: from yangzhon-virtual.bj.intel.com (HELO yangzhon-Virtual) ([10.238.144.101]) by orsmga007-auth.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-SHA256; 30 Nov 2021 04:30:23 -0800 Date: Tue, 30 Nov 2021 20:15:36 +0800 From: Yang Zhong To: qemu-devel@nongnu.org Subject: Re: unable to execute QEMU command 'qom-get': Property 'sgx-epc.unavailable-features' not found Message-ID: <20211130121536.GA32686@yangzhon-Virtual> References: <20211125124722.GA25401@yangzhon-Virtual> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20211125124722.GA25401@yangzhon-Virtual> User-Agent: Mutt/1.5.21 (2010-09-15) Received-SPF: pass client-ip=134.134.136.24; envelope-from=yang.zhong@intel.com; helo=mga09.intel.com X-Spam_score_int: -41 X-Spam_score: -4.2 X-Spam_bar: ---- X-Spam_report: (-4.2 / 5.0 requ) BAYES_00=-1.9, RCVD_IN_DNSWL_MED=-2.3, RCVD_IN_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: yang.zhong@intel.com, pbonzini@redhat.com, eblake@redhat.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Thu, Nov 25, 2021 at 08:47:22PM +0800, Yang Zhong wrote: > Hello Paolo, > > Our customer used the Libvirt XML to start a SGX VM, but failed. > > libvirt.libvirtError: internal error: unable to execute QEMU command 'qom-get': Property 'sgx-epc.unavailable-features' not found > > The XML file, > > > > > > > > > > The new compound property command should be located in /machine path, > which are different with old command '-sgx-epc id=epc1,memdev=mem1'. > > I also tried this from Qemu monitor tool, > (qemu) qom-list /machine > type (string) > kernel (string) > ...... > sgx-epc (SgxEPC) > ...... > sgx-epc[0] (child) > ...... > > We can find sgx-epc from /machine list. > This issue is clear now, which is caused by Libvirt to get the CPU's unavailable-features by below command: {"execute":"qom-get","arguments":{"path":"/machine/unattached/device[0]","property":"unavailable-features"} but in SGX vm, since the sgx is initialized before VCPU because sgx need set the virtual EPC info in the cpuid. So the /machine/unattached/device[0] is occupied by sgx, which fail to get the unvailable-features from /machine/unattached/device[0]. We need fix this issue, but this can be done in Qemu or Libvirt side. 1) Libvirt side If the libvirt support SGX EPCs, libvirt can use /machine/unattached/device[n] to check "unavailable-features". n is the next number of sgx's unattached_count. 2) Qemu side One temp patch to create one /sgx in the /machine in the device_set_realized() diff --git a/hw/core/qdev.c b/hw/core/qdev.c index 84f3019440..4154eef0d8 100644 --- a/hw/core/qdev.c +++ b/hw/core/qdev.c @@ -497,7 +497,7 @@ static void device_set_realized(Object *obj, bool value, Error **errp) NamedClockList *ncl; Error *local_err = NULL; bool unattached_parent = false; - static int unattached_count; + static int unattached_count, sgx_count; if (dev->hotplugged && !dc->hotpluggable) { error_setg(errp, QERR_DEVICE_NO_HOTPLUG, object_get_typename(obj)); @@ -509,7 +509,15 @@ static void device_set_realized(Object *obj, bool value, Error **errp) goto fail; } - if (!obj->parent) { + if (!obj->parent && !strcmp(object_get_typename(obj), "sgx-epc")) { + gchar *name = g_strdup_printf("device[%d]", sgx_count++); + + object_property_add_child(container_get(qdev_get_machine(), + "/sgx"), + name, obj); + unattached_parent = true; + g_free(name); + } else if (!obj->parent) { gchar *name = g_strdup_printf("device[%d]", unattached_count++); object_property_add_child(container_get(qdev_get_machine() This patch can make sure vcpu is still /machine/unattached/device[0]. Which solution is best? thanks! Yang > I am not familiar with Libvirt side, would you please suggest how to implement > this compound command in the XML file? thanks a lot! > > Regards, > > Yang >