From patchwork Thu Jul 6 19:12:26 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Eugenio Perez Martin X-Patchwork-Id: 13304081 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 3AC3FEB64D9 for ; Thu, 6 Jul 2023 19:14:14 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qHUPN-00066B-Ak; Thu, 06 Jul 2023 15:12:53 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qHUPL-00065N-GN for qemu-devel@nongnu.org; Thu, 06 Jul 2023 15:12:51 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qHUPJ-0003it-Uf for qemu-devel@nongnu.org; Thu, 06 Jul 2023 15:12:51 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1688670769; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=WZ0T9Bj7ivsWGJG0O+gF5mf9U2T53/pSkGsxT8Ys2kQ=; b=TggXe6CH34RnY5r0I2YYqSWprQIS0XT8fb8BlLPRnebO4aJeLFX3UhYiOw+Ph+ZZkwgL7H OPdtaWTRLZKl2/xSxWXydnFuM/+29AoMS8iSP+QUjlr8xXp9dHlUIzdH845Y2kqF3yau+w 7+aqdmODwG8PMNfH5mB0XHJsr7TRPzg= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-250-9lz0WDnDNWq3RbPewj_Wkw-1; Thu, 06 Jul 2023 15:12:43 -0400 X-MC-Unique: 9lz0WDnDNWq3RbPewj_Wkw-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.rdu2.redhat.com [10.11.54.2]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 43FF7104458E; Thu, 6 Jul 2023 19:12:43 +0000 (UTC) Received: from eperezma.remote.csb (unknown [10.39.194.147]) by smtp.corp.redhat.com (Postfix) with ESMTP id 2789D4087C6A; Thu, 6 Jul 2023 19:12:41 +0000 (UTC) From: =?utf-8?q?Eugenio_P=C3=A9rez?= To: qemu-devel@nongnu.org Cc: Laurent Vivier , "Michael S. Tsirkin" , Cindy Lu , si-wei.liu@oracle.com, Stefano Garzarella , Shannon Nelson , Gautam Dawar , Jason Wang , Harpreet Singh Anand , Parav Pandit , Dragos Tatulea , Zhu Lingshan , Lei Yang Subject: [RFC PATCH 5/6] vdpa: delay enable of data vqs Date: Thu, 6 Jul 2023 21:12:26 +0200 Message-Id: <20230706191227.835526-6-eperezma@redhat.com> In-Reply-To: <20230706191227.835526-1-eperezma@redhat.com> References: <20230706191227.835526-1-eperezma@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.2 Received-SPF: pass client-ip=170.10.133.124; envelope-from=eperezma@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 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_NONE=-0.0001, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 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: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org To restore the device at the destination of a live migration we send the commands through control virtqueue. For a device to read CVQ it must have received the DRIVER_OK status bit. However this opens a window where the device could start receiving packets in rx queue 0 before it receives the RSS configuration. To avoid that, we do not send vring_enable until all configuration is used by the device. Signed-off-by: Eugenio Pérez --- net/vhost-vdpa.c | 25 ++++++++++++++++++++++++- 1 file changed, 24 insertions(+), 1 deletion(-) diff --git a/net/vhost-vdpa.c b/net/vhost-vdpa.c index 536bab8613..d5970e9f06 100644 --- a/net/vhost-vdpa.c +++ b/net/vhost-vdpa.c @@ -739,6 +739,13 @@ static int vhost_vdpa_net_load(NetClientState *nc) return r; } + for (int i = 0; i < v->dev->vq_index; ++i) { + r = vhost_vdpa_set_vring_ready(v, i); + if (unlikely(r)) { + return r; + } + } + return 0; } @@ -826,9 +833,25 @@ static const VhostShadowVirtqueueOps vhost_vdpa_net_svq_ops = { .avail_handler = vhost_vdpa_net_handle_ctrl_avail, }; +/** + * Check if a vhost_vdpa device should enable before DRIVER_OK + * + * CVQ must always start first if we want to restore the state safely. Do not + * start data vqs if the device has CVQ. + */ static bool vhost_vdpa_should_enable(const struct vhost_vdpa *v) { - return true; + struct vhost_dev *dev = v->dev; + + if (!dev->vq_index_end % 2) { + /* vDPA device does not have CVQ */ + return true; + } + + /* + * We're evaluating CVQ, enable to send control cmds to load device state. + */ + return dev->vq_index + 1 == dev->vq_index_end; } static const VhostVDPAVirtIOOps vhost_vdpa_virtio_net_ops = {