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=-16.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 D461EC433E6 for ; Sat, 13 Feb 2021 03:00:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A372264E9C for ; Sat, 13 Feb 2021 03:00:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231699AbhBMCtZ (ORCPT ); Fri, 12 Feb 2021 21:49:25 -0500 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:12814 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231394AbhBMCtY (ORCPT ); Fri, 12 Feb 2021 21:49:24 -0500 Received: from pps.filterd (m0098399.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 11D2hkvP076716 for ; Fri, 12 Feb 2021 21:48:44 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ibm.com; h=from : to : cc : subject : date : message-id : mime-version : content-transfer-encoding; s=pp1; bh=scnQzp5kbnQ/E+M/CpD3o4+QE/qZswcIQD/Sq5gQGOo=; b=Jni7iT682ScQXN/54iDDj6pl/wvegvDiws2+NF+uT9WYkOblinc8/v8edHAblS3nTYXs ocj3L0kImtzpC+xxnznImJyzsBvphhTRBHDowh/DWRggYpM5ugloj7FLepatOXgPHP9s +2mRD9SGcoAVw3DNjP5kofHei5h9PTBRtSXHFlXQVmN3MVA0tzdv/ZIxIJgYY79MuGJs i4bAQtjgzWXrnBj2AmAtiowKD3St919BIRTlvdFac0DQa5nb9INzIY6ZzzaiBcGhPEwR 3lgT4QIkY2IpXezTvO4GngyTgxo++5FFlEoZA7I1XXrXj68DsXrFMgMxEuxXwx4IPak1 hw== Received: from ppma01dal.us.ibm.com (83.d6.3fa9.ip4.static.sl-reverse.com [169.63.214.131]) by mx0a-001b2d01.pphosted.com with ESMTP id 36p680g2qk-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT) for ; Fri, 12 Feb 2021 21:48:44 -0500 Received: from pps.filterd (ppma01dal.us.ibm.com [127.0.0.1]) by ppma01dal.us.ibm.com (8.16.0.42/8.16.0.42) with SMTP id 11D2knv5021479 for ; Sat, 13 Feb 2021 02:48:43 GMT Received: from b03cxnp07028.gho.boulder.ibm.com (b03cxnp07028.gho.boulder.ibm.com [9.17.130.15]) by ppma01dal.us.ibm.com with ESMTP id 36hjradv8a-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT) for ; Sat, 13 Feb 2021 02:48:43 +0000 Received: from b03ledav006.gho.boulder.ibm.com (b03ledav006.gho.boulder.ibm.com [9.17.130.237]) by b03cxnp07028.gho.boulder.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 11D2mf1g25100652 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Sat, 13 Feb 2021 02:48:41 GMT Received: from b03ledav006.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id AF32DC6055; Sat, 13 Feb 2021 02:48:41 +0000 (GMT) Received: from b03ledav006.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id CB735C605A; Sat, 13 Feb 2021 02:48:40 +0000 (GMT) Received: from pompom.ibm.com (unknown [9.80.198.213]) by b03ledav006.gho.boulder.ibm.com (Postfix) with ESMTP; Sat, 13 Feb 2021 02:48:40 +0000 (GMT) From: Lijun Pan To: netdev@vger.kernel.org Cc: sukadev@linux.ibm.com, drt@linux.ibm.com, Lijun Pan , Thomas Falcon Subject: [PATCH net] ibmvnic: add memory barrier to protect long term buffer Date: Fri, 12 Feb 2021 20:48:40 -0600 Message-Id: <20210213024840.56036-1-ljp@linux.ibm.com> X-Mailer: git-send-email 2.22.0 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-TM-AS-GCONF: 00 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.369,18.0.737 definitions=2021-02-13_01:2021-02-12,2021-02-12 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 adultscore=0 mlxlogscore=916 clxscore=1015 impostorscore=0 suspectscore=0 mlxscore=0 bulkscore=0 priorityscore=1501 lowpriorityscore=0 spamscore=0 phishscore=0 malwarescore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2009150000 definitions=main-2102130022 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org dma_rmb() barrier is added to load the long term buffer before copying it to socket buffer; and dma_wmb() barrier is added to update the long term buffer before it being accessed by VIOS (virtual i/o server). Fixes: 032c5e82847a ("Driver for IBM System i/p VNIC protocol") Signed-off-by: Lijun Pan Acked-by: Thomas Falcon --- drivers/net/ethernet/ibm/ibmvnic.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/net/ethernet/ibm/ibmvnic.c b/drivers/net/ethernet/ibm/ibmvnic.c index c8b0d99608d5..cd201f89ce6c 100644 --- a/drivers/net/ethernet/ibm/ibmvnic.c +++ b/drivers/net/ethernet/ibm/ibmvnic.c @@ -1705,6 +1705,9 @@ static netdev_tx_t ibmvnic_xmit(struct sk_buff *skb, struct net_device *netdev) skb_copy_from_linear_data(skb, dst, skb->len); } + /* post changes to long_term_buff *dst before VIOS accessing it */ + dma_wmb(); + tx_pool->consumer_index = (tx_pool->consumer_index + 1) % tx_pool->num_buffers; @@ -2544,6 +2547,8 @@ static int ibmvnic_poll(struct napi_struct *napi, int budget) offset = be16_to_cpu(next->rx_comp.off_frame_data); flags = next->rx_comp.flags; skb = rx_buff->skb; + /* load long_term_buff before copying to skb */ + dma_rmb(); skb_copy_to_linear_data(skb, rx_buff->data + offset, length); -- 2.23.0