From patchwork Tue Jul 2 14:07:29 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: "Michael S. Tsirkin" X-Patchwork-Id: 13719718 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 28A53C30658 for ; Tue, 2 Jul 2024 14:09:58 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1sOeAe-00024x-Hk; Tue, 02 Jul 2024 10:07:48 -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 1sOeAa-00023R-T6 for qemu-devel@nongnu.org; Tue, 02 Jul 2024 10:07:44 -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 1sOeAY-0007x4-JN for qemu-devel@nongnu.org; Tue, 02 Jul 2024 10:07:44 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1719929260; 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=Bf3inGfH3C1OrX/KdJFaqQvDHDePnfUDWhDjBaZ52tk=; b=O3j5J0v0vFSMiLulKM068Y8mV2J+86e5fbBWGJYnSwvIT+SvwfoZd9BVtJPNEb82PanvTr e3xtifQpMqxon1cx2bbaq2DCgkn/jef5fhNSeFHre+27qhez6FPf/Yd1hNQM7LmwKzv481 qsADgfDWmU2hyeIrm4R+l+bPTQThueY= Received: from mail-wm1-f72.google.com (mail-wm1-f72.google.com [209.85.128.72]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-616-MJ4QSHjUOX-fLj2B6pW1HA-1; Tue, 02 Jul 2024 10:07:35 -0400 X-MC-Unique: MJ4QSHjUOX-fLj2B6pW1HA-1 Received: by mail-wm1-f72.google.com with SMTP id 5b1f17b1804b1-42567dbbd20so31657415e9.0 for ; Tue, 02 Jul 2024 07:07:35 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1719929254; x=1720534054; h=in-reply-to:content-transfer-encoding:content-disposition :mime-version:references:message-id:subject:cc:to:from:date :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=Bf3inGfH3C1OrX/KdJFaqQvDHDePnfUDWhDjBaZ52tk=; b=InVJs3fBH8s/6B/1pDV58pE0QXgadSZRvJZsempkgwv9+x/jdTwu7GgNMP4r1Ra72C W/vM/Hspb8lot8yyD6+RlDDjL7rSt0+jpXCNJYILQ5rnVgp3x2u7KMdpFrPXRNfCpGDF e+BrjtezYR1zXruYjjV/DnhzzLtcY8PCCm7KAMNk3NUKJUTHf7Po5IPQ3iZpXWCujOpl BmnRwCctgk1AwWQxX8RG6W3TIAduGaB0SSAezIwwmf/5GlaJtBOLm2vzKEaH4VjqGt0X 2h8T4Vz6nzd+ZfF6uLDNi322RgL3a9rzcraUdYjLjYkzrLYFYTFcAvbJIOm0+I4DOElX eMSg== X-Gm-Message-State: AOJu0YwloPrTHdOIl9J2K7uUSU+dhX5QEN85z6vW7oAno3OSIiUkfShM SRhYT4r6caUxcqjZhk/g3IOUrFNYXlCIQVrqByB8nylKG46FosTTDOZMIEuUMrTyD02RsbeZRYf X7nL3cpAR5xHcHxaNv424A5hDshmJCZQp6EMsk//m6ceGPcn+mI5hixj62qrC+t8XbVjjsmsnQu bIYPX3JZpQgb/g/bLG/5P2UdiuUV03qQ== X-Received: by 2002:a05:600c:4da1:b0:425:64c4:e016 with SMTP id 5b1f17b1804b1-4257a0098c1mr58126755e9.12.1719929254050; Tue, 02 Jul 2024 07:07:34 -0700 (PDT) X-Google-Smtp-Source: AGHT+IGgqgXXTAj0rm4CAIuShkn4R+gTJ9PgwVNThobgo59qdwLkqdpgk8+yeCqyuWs3dnNY5m1lFA== X-Received: by 2002:a05:600c:4da1:b0:425:64c4:e016 with SMTP id 5b1f17b1804b1-4257a0098c1mr58126515e9.12.1719929253494; Tue, 02 Jul 2024 07:07:33 -0700 (PDT) Received: from redhat.com ([2a02:14f:1f5:eadd:8c31:db01:9d01:7604]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-4256af55cccsm199945575e9.16.2024.07.02.07.07.31 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 02 Jul 2024 07:07:32 -0700 (PDT) Date: Tue, 2 Jul 2024 10:07:29 -0400 From: "Michael S. Tsirkin" To: qemu-devel@nongnu.org Cc: Peter Maydell , Wafer , Jason Wang , Eugenio =?utf-8?b?UMOpcmV6?= Subject: [PULL 11/91] hw/virtio: Fix obtain the buffer id from the last descriptor Message-ID: <33abfea239592a706e98269b01c0096249612ea4.1719929191.git.mst@redhat.com> References: MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: X-Mailer: git-send-email 2.27.0.106.g8ac3dc51b1 X-Mutt-Fcc: =sent Received-SPF: pass client-ip=170.10.133.124; envelope-from=mst@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 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 From: Wafer The virtio-1.3 specification writes: 2.8.6 Next Flag: Descriptor Chaining Buffer ID is included in the last descriptor in the list. If the feature (_F_INDIRECT_DESC) has been negotiated, install only one descriptor in the virtqueue. Therefor the buffer id should be obtained from the first descriptor. In descriptor chaining scenarios, the buffer id should be obtained from the last descriptor. Fixes: 86044b24e8 ("virtio: basic packed virtqueue support") Signed-off-by: Wafer Reviewed-by: Jason Wang Reviewed-by: Eugenio Pérez Acked-by: Jason Wang Message-Id: <20240510072753.26158-2-wafer@jaguarmicro.com> Reviewed-by: Michael S. Tsirkin Signed-off-by: Michael S. Tsirkin --- hw/virtio/virtio.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c index 28cd406e16..3678ec2f88 100644 --- a/hw/virtio/virtio.c +++ b/hw/virtio/virtio.c @@ -1745,6 +1745,11 @@ static void *virtqueue_packed_pop(VirtQueue *vq, size_t sz) &indirect_desc_cache); } while (rc == VIRTQUEUE_READ_DESC_MORE); + if (desc_cache != &indirect_desc_cache) { + /* Buffer ID is included in the last descriptor in the list. */ + id = desc.id; + } + /* Now copy what we have collected and mapped */ elem = virtqueue_alloc_element(sz, out_num, in_num); for (i = 0; i < out_num; i++) {