From patchwork Thu Nov 17 16:55:52 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Stefan Hajnoczi X-Patchwork-Id: 1705217 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@legolas.ozlabs.org Authentication-Results: legolas.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=) Authentication-Results: legolas.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=KTMX5UKU; dkim-atps=neutral Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-ECDSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by legolas.ozlabs.org (Postfix) with ESMTPS id 4NCmKL0v23z23mR for ; Fri, 18 Nov 2022 03:56:37 +1100 (AEDT) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1oviBQ-0005pd-04; Thu, 17 Nov 2022 11:56:12 -0500 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 1oviBO-0005oN-Em for qemu-devel@nongnu.org; Thu, 17 Nov 2022 11:56:10 -0500 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 1oviBN-0007m0-2H for qemu-devel@nongnu.org; Thu, 17 Nov 2022 11:56:10 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1668704168; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=DvJ4lkdX+wmID6ozOrP92erLwYqSbxWQcDGOd3PHcUU=; b=KTMX5UKU84Q2kbGRCm1Odm9lkxOMZNZjzowRJNGoaTKkI3v/VleXpBQHJkF10SyqSr60cR gurQVm5WVp8nrMQNuyYsDo8Qq0qr887hzWrmb0vySda4/1OvqPGsSfJN0rKxMJqjNc/whf tCgmY5pzUI60KkEyTRKLtJtqdCfhSj0= 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-104--kvRigWZP_GBrk0OOebSOQ-1; Thu, 17 Nov 2022 11:56:03 -0500 X-MC-Unique: -kvRigWZP_GBrk0OOebSOQ-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.rdu2.redhat.com [10.11.54.8]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 4D311857F92; Thu, 17 Nov 2022 16:56:03 +0000 (UTC) Received: from localhost (unknown [10.39.193.61]) by smtp.corp.redhat.com (Postfix) with ESMTP id BA90EC1E88E; Thu, 17 Nov 2022 16:56:02 +0000 (UTC) From: Stefan Hajnoczi To: qemu-devel@nongnu.org Cc: Tobias Fiebig , Jason Wang , qemu-stable@nongnu.org, Stefan Hajnoczi Subject: [PATCH for-7.2 v3 1/3] rtl8139: avoid clobbering tx descriptor bits Date: Thu, 17 Nov 2022 11:55:52 -0500 Message-Id: <20221117165554.1773409-2-stefanha@redhat.com> In-Reply-To: <20221117165554.1773409-1-stefanha@redhat.com> References: <20221117165554.1773409-1-stefanha@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.8 Received-SPF: pass client-ip=170.10.133.124; envelope-from=stefanha@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_H2=-0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=unavailable 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-bounces+incoming=patchwork.ozlabs.org@nongnu.org The device turns the Tx Descriptor into a Tx Status descriptor after fully reading the descriptor. This involves clearing Tx Own (bit 31) to indicate that the driver has ownership of the descriptor again as well as several other bits. The code keeps the first dword of the Tx Descriptor in the txdw0 local variable. txdw0 is reused to build the first word of the Tx Status descriptor. Later on the code uses txdw0 again, incorrectly assuming that it still contains the first dword of the Tx Descriptor. The tx offloading code misbehaves because it sees bogus bits in txdw0. Use a separate local variable for Tx Status and preserve Tx Descriptor in txdw0. Signed-off-by: Stefan Hajnoczi Reviewed-by: Philippe Mathieu-Daudé Acked-by: Jason Wang --- hw/net/rtl8139.c | 17 ++++++++++------- 1 file changed, 10 insertions(+), 7 deletions(-) diff --git a/hw/net/rtl8139.c b/hw/net/rtl8139.c index e6643e3c9d..ffef3789b5 100644 --- a/hw/net/rtl8139.c +++ b/hw/net/rtl8139.c @@ -2027,18 +2027,21 @@ static int rtl8139_cplus_transmit_one(RTL8139State *s) s->currCPlusTxDesc = 0; } + /* Build the Tx Status Descriptor */ + uint32_t tx_status = txdw0; + /* transfer ownership to target */ - txdw0 &= ~CP_TX_OWN; + tx_status &= ~CP_TX_OWN; /* reset error indicator bits */ - txdw0 &= ~CP_TX_STATUS_UNF; - txdw0 &= ~CP_TX_STATUS_TES; - txdw0 &= ~CP_TX_STATUS_OWC; - txdw0 &= ~CP_TX_STATUS_LNKF; - txdw0 &= ~CP_TX_STATUS_EXC; + tx_status &= ~CP_TX_STATUS_UNF; + tx_status &= ~CP_TX_STATUS_TES; + tx_status &= ~CP_TX_STATUS_OWC; + tx_status &= ~CP_TX_STATUS_LNKF; + tx_status &= ~CP_TX_STATUS_EXC; /* update ring data */ - val = cpu_to_le32(txdw0); + val = cpu_to_le32(tx_status); pci_dma_write(d, cplus_tx_ring_desc, (uint8_t *)&val, 4); /* Now decide if descriptor being processed is holding the last segment of packet */