From patchwork Thu Aug 4 18:17:12 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Eugenio Perez Martin X-Patchwork-Id: 1663791 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: bilbo.ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256 header.s=mimecast20190719 header.b=W+2tf65P; dkim-atps=neutral Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org (client-ip=209.51.188.17; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) 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 bilbo.ozlabs.org (Postfix) with ESMTPS id 4LzHCd43pDz9rx7 for ; Fri, 5 Aug 2022 04:23:09 +1000 (AEST) Received: from localhost ([::1]:60090 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1oJfUx-0003wz-Bk for incoming@patchwork.ozlabs.org; Thu, 04 Aug 2022 14:23:07 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:60842) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1oJfPu-0005yG-Nf for qemu-devel@nongnu.org; Thu, 04 Aug 2022 14:17:54 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]:39037) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1oJfPr-0001EO-7p for qemu-devel@nongnu.org; Thu, 04 Aug 2022 14:17:53 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1659637070; 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=mFcSWUZrd/1meZg3dITq3TzQyarfrxoNesnu+w7BZmQ=; b=W+2tf65PxDJVcxrkGfwNaEG8clYD/cZDE+1BPns33u76WZZLgSP1yaeTUxfe9vZgfKRx1S w+egZKZwdrYSULbgTzd6So3+bDSycUKdhENUgydGQiomzY11T+f6wsED0gBmhm8qLibM9e 5O77VaoxWB4WS2JCPlEStfvOccRmQ28= 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-35-4ybmrivsN8Cw15iNeI7m3g-1; Thu, 04 Aug 2022 14:17:48 -0400 X-MC-Unique: 4ybmrivsN8Cw15iNeI7m3g-1 Received: from smtp.corp.redhat.com (int-mx09.intmail.prod.int.rdu2.redhat.com [10.11.54.9]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id DC856800DBE; Thu, 4 Aug 2022 18:17:34 +0000 (UTC) Received: from eperezma.remote.csb (unknown [10.39.192.132]) by smtp.corp.redhat.com (Postfix) with ESMTP id C42B2492C3B; Thu, 4 Aug 2022 18:17:31 +0000 (UTC) From: =?utf-8?q?Eugenio_P=C3=A9rez?= To: qemu-devel@nongnu.org Cc: Stefano Garzarella , "Gonglei (Arei)" , Cornelia Huck , Liuxiangdong , "Michael S. Tsirkin" , Jason Wang , Gautam Dawar , Laurent Vivier , Eli Cohen , Zhu Lingshan , Cindy Lu , Stefan Hajnoczi , Parav Pandit , Paolo Bonzini , Harpreet Singh Anand , Eric Blake , Markus Armbruster Subject: [PATCH v6 02/12] vhost: use SVQ element ndescs instead of opaque data for desc validation Date: Thu, 4 Aug 2022 20:17:12 +0200 Message-Id: <20220804181722.701067-3-eperezma@redhat.com> In-Reply-To: <20220804181722.701067-1-eperezma@redhat.com> References: <20220804181722.701067-1-eperezma@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.85 on 10.11.54.9 Received-SPF: pass client-ip=170.10.129.124; envelope-from=eperezma@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -28 X-Spam_score: -2.9 X-Spam_bar: -- X-Spam_report: (-2.9 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.082, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, 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+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" Since we're going to allow SVQ to add elements without the guest's knowledge and without its own VirtQueueElement, it's easier to check if an element is a valid head checking a different thing than the VirtQueueElement. Signed-off-by: Eugenio Pérez --- hw/virtio/vhost-shadow-virtqueue.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/hw/virtio/vhost-shadow-virtqueue.c b/hw/virtio/vhost-shadow-virtqueue.c index ffd2b2c972..e6eebd0e8d 100644 --- a/hw/virtio/vhost-shadow-virtqueue.c +++ b/hw/virtio/vhost-shadow-virtqueue.c @@ -414,7 +414,7 @@ static VirtQueueElement *vhost_svq_get_buf(VhostShadowVirtqueue *svq, return NULL; } - if (unlikely(!svq->desc_state[used_elem.id].elem)) { + if (unlikely(!svq->desc_state[used_elem.id].ndescs)) { qemu_log_mask(LOG_GUEST_ERROR, "Device %s says index %u is used, but it was not available", svq->vdev->name, used_elem.id); @@ -422,6 +422,7 @@ static VirtQueueElement *vhost_svq_get_buf(VhostShadowVirtqueue *svq, } num = svq->desc_state[used_elem.id].ndescs; + svq->desc_state[used_elem.id].ndescs = 0; last_used_chain = vhost_svq_last_desc_of_chain(svq, num, used_elem.id); svq->desc_next[last_used_chain] = svq->free_head; svq->free_head = used_elem.id;