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 X-Spam-Level: X-Spam-Status: No, score=-17.3 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 966C6C433ED for ; Tue, 6 Apr 2021 15:19:44 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id E0193611C1 for ; Tue, 6 Apr 2021 15:19:43 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E0193611C1 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:43166 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lTnUU-0000Vv-Ko for qemu-devel@archiver.kernel.org; Tue, 06 Apr 2021 11:19:42 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:53234) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lTnJM-0005PS-T3 for qemu-devel@nongnu.org; Tue, 06 Apr 2021 11:08:12 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:57188) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lTnJI-0000oF-4b for qemu-devel@nongnu.org; Tue, 06 Apr 2021 11:08:12 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1617721687; h=from:from:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=TKsNzzMuohctfFO/avnN4KNnzjNXmgyIqLXRL4UEPwI=; b=SmhJJs74+fEvtuxYweErvAKczSZEIhAkNwamUdGAzKVZgCyeTzh4AzERbs1319WZSGrQIq +YytyHbkcpcP3GUQbctF3Seji7kJK14eu3nHgWwDQV8ZmoPO/ViMx0Iog5q07t6Lk+H9Ym Sy2DBz4pOfBShrLzn/sBJ8WQBch9yk8= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-416-yiuu9XH-O--YU_ZHH6UmGg-1; Tue, 06 Apr 2021 11:07:33 -0400 X-MC-Unique: yiuu9XH-O--YU_ZHH6UmGg-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 0749618C8C20; Tue, 6 Apr 2021 15:07:33 +0000 (UTC) Received: from redhat.com (ovpn-114-172.ams2.redhat.com [10.36.114.172]) by smtp.corp.redhat.com (Postfix) with ESMTPS id AE3B05D9D0; Tue, 6 Apr 2021 15:07:28 +0000 (UTC) Date: Tue, 6 Apr 2021 16:07:25 +0100 From: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= To: "Michael S. Tsirkin" , Peter Maydell , qemu-devel@nongnu.org, Igor Mammedov Subject: Re: [PULL v2 11/19] pci: acpi: ensure that acpi-index is unique Message-ID: References: <20210322225907.541943-1-mst@redhat.com> <20210322225907.541943-12-mst@redhat.com> MIME-Version: 1.0 In-Reply-To: User-Agent: Mutt/2.0.5 (2021-01-21) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=berrange@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit Received-SPF: pass client-ip=170.10.133.124; envelope-from=berrange@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -27 X-Spam_score: -2.8 X-Spam_bar: -- X-Spam_report: (-2.8 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H4=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: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Tue, Apr 06, 2021 at 03:54:24PM +0100, Daniel P. Berrangé wrote: > On Mon, Mar 22, 2021 at 07:00:18PM -0400, Michael S. Tsirkin wrote: > > From: Igor Mammedov > > > > it helps to avoid device naming conflicts when guest OS is > > configured to use acpi-index for naming. > > Spec ialso says so: > > > > PCI Firmware Specification Revision 3.2 > > 4.6.7. _DSM for Naming a PCI or PCI Express Device Under Operating Systems > > " > > Instance number must be unique under \_SB scope. This instance number does not have to > > be sequential in a given system configuration. > > " > > > > Signed-off-by: Igor Mammedov > > Message-Id: <20210315180102.3008391-4-imammedo@redhat.com> > > Reviewed-by: Michael S. Tsirkin > > Signed-off-by: Michael S. Tsirkin > > --- > > hw/acpi/pcihp.c | 46 ++++++++++++++++++++++++++++++++++++++++++++++ > > 1 file changed, 46 insertions(+) > > > > diff --git a/hw/acpi/pcihp.c b/hw/acpi/pcihp.c > > index ceab287bd3..f4cb3c979d 100644 > > --- a/hw/acpi/pcihp.c > > +++ b/hw/acpi/pcihp.c > > @@ -52,6 +52,21 @@ typedef struct AcpiPciHpFind { > > PCIBus *bus; > > } AcpiPciHpFind; > > > > +static gint g_cmp_uint32(gconstpointer a, gconstpointer b, gpointer user_data) > > +{ > > + return a - b; > > +} > > + > > +static GSequence *pci_acpi_index_list(void) > > +{ > > + static GSequence *used_acpi_index_list; > > + > > + if (!used_acpi_index_list) { > > + used_acpi_index_list = g_sequence_new(NULL); > > + } > > + return used_acpi_index_list; > > +} > > + > > static int acpi_pcihp_get_bsel(PCIBus *bus) > > { > > Error *local_err = NULL; > > @@ -277,6 +292,23 @@ void acpi_pcihp_device_pre_plug_cb(HotplugHandler *hotplug_dev, > > ONBOARD_INDEX_MAX); > > return; > > } > > + > > + /* > > + * make sure that acpi-index is unique across all present PCI devices > > + */ > > + if (pdev->acpi_index) { > > + GSequence *used_indexes = pci_acpi_index_list(); > > + > > + if (g_sequence_lookup(used_indexes, GINT_TO_POINTER(pdev->acpi_index), > > + g_cmp_uint32, NULL)) { > > + error_setg(errp, "a PCI device with acpi-index = %" PRIu32 > > + " already exist", pdev->acpi_index); > > + return; > > + } > > + g_sequence_insert_sorted(used_indexes, > > + GINT_TO_POINTER(pdev->acpi_index), > > + g_cmp_uint32, NULL); > > + } > > This doesn't appear to ensure uniqueness when using PCIe topologies: > > $ ./build/x86_64-softmmu/qemu-system-x86_64 \ > -device virtio-net,acpi-index=100 \ > -device virtio-net,acpi-index=100 > qemu-system-x86_64: -device virtio-net,acpi-index=100: a PCI device with acpi-index = 100 already exist > > $ ./build/x86_64-softmmu/qemu-system-x86_64 \ > -M q35 \ > -device virtio-net,acpi-index=100 > -device virtio-net,acpi-index=100 > ....happily running.... In fact the entire concept doesn't appear to work with Q35 at all as implemented. The 'acpi_index' file in the guest OS never gets created and the NICs are still called 'eth0', 'eth1' Only with i440fx can I can the "enoNNN" based naming to work with acpi-index set from QEMU Regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|