From patchwork Mon Jan 25 23:20:23 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lijun Pan X-Patchwork-Id: 370450 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 0A3EFC433DB for ; Mon, 25 Jan 2021 23:21:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B69E621D93 for ; Mon, 25 Jan 2021 23:21:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732760AbhAYXVo (ORCPT ); Mon, 25 Jan 2021 18:21:44 -0500 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:3642 "EHLO mx0b-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732103AbhAYXVJ (ORCPT ); Mon, 25 Jan 2021 18:21:09 -0500 Received: from pps.filterd (m0098421.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 10PN1VbC153233 for ; Mon, 25 Jan 2021 18:20:26 -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=3WsESBR/aCHMcKLq5YFPFoi6SiBoWt6KhXiyV66ad0w=; b=BjYPicyheb/c9t6C1tmvvprq06w27+7SJnQNEJgjPCkLFBD8qADnD3MIGg0Hl/dwrcI4 v4l8pBXjhVxbjPQbKAj0AqufTD6ccMcWIyvt36Uw47NXMa49AZhPeMInoUvtXe4I8e8Y 7X6ylQDfN0xyBB9ZliI4s0cn+2JgXVv6gYxHIRYQPejEmWkZq29RthwxZstTqzhQJimS kSjA3a5gJX9U0pGHrFemi0RLjoMSuSGklO8jCKrcs3DGY32M6Gum5NQNe6Czi8Um5v56 xPCF1wZxDa2+vT0Ty5MZrDAGJWwTjpZBHxkyhgJ0Be9vnAxvATF84+Nzqgs2LZfma/vE 3g== Received: from ppma03dal.us.ibm.com (b.bd.3ea9.ip4.static.sl-reverse.com [169.62.189.11]) by mx0a-001b2d01.pphosted.com with ESMTP id 36a6d29jra-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT) for ; Mon, 25 Jan 2021 18:20:26 -0500 Received: from pps.filterd (ppma03dal.us.ibm.com [127.0.0.1]) by ppma03dal.us.ibm.com (8.16.0.42/8.16.0.42) with SMTP id 10PNCdtW020469 for ; Mon, 25 Jan 2021 23:20:26 GMT Received: from b03cxnp07027.gho.boulder.ibm.com (b03cxnp07027.gho.boulder.ibm.com [9.17.130.14]) by ppma03dal.us.ibm.com with ESMTP id 368be8xjq5-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT) for ; Mon, 25 Jan 2021 23:20:26 +0000 Received: from b03ledav003.gho.boulder.ibm.com (b03ledav003.gho.boulder.ibm.com [9.17.130.234]) by b03cxnp07027.gho.boulder.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 10PNKOpw8585688 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 25 Jan 2021 23:20:24 GMT Received: from b03ledav003.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 944816A04D; Mon, 25 Jan 2021 23:20:24 +0000 (GMT) Received: from b03ledav003.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 1B8FB6A066; Mon, 25 Jan 2021 23:20:24 +0000 (GMT) Received: from pompom.ibm.com (unknown [9.80.236.90]) by b03ledav003.gho.boulder.ibm.com (Postfix) with ESMTP; Mon, 25 Jan 2021 23:20:23 +0000 (GMT) From: Lijun Pan To: netdev@vger.kernel.org Cc: Lijun Pan Subject: [PATCH net v2] ibmvnic: Ensure that CRQ entry read are correctly ordered Date: Mon, 25 Jan 2021 17:20:23 -0600 Message-Id: <20210125232023.78649-1-ljp@linux.ibm.com> X-Mailer: git-send-email 2.22.0 MIME-Version: 1.0 X-TM-AS-GCONF: 00 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.343, 18.0.737 definitions=2021-01-25_10:2021-01-25,2021-01-25 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 mlxlogscore=932 phishscore=0 adultscore=0 clxscore=1015 lowpriorityscore=0 suspectscore=0 bulkscore=0 spamscore=0 mlxscore=0 malwarescore=0 priorityscore=1501 impostorscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2009150000 definitions=main-2101250112 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Ensure that received Command-Response Queue (CRQ) entries are properly read in order by the driver. dma_rmb barrier has been added before accessing the CRQ descriptor to ensure the entire descriptor is read before processing. Fixes: 032c5e82847a ("Driver for IBM System i/p VNIC protocol") Signed-off-by: Lijun Pan --- v2: drop dma_wmb according to Jakub's opinion drivers/net/ethernet/ibm/ibmvnic.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/drivers/net/ethernet/ibm/ibmvnic.c b/drivers/net/ethernet/ibm/ibmvnic.c index 9778c83150f1..d84369bd5fc9 100644 --- a/drivers/net/ethernet/ibm/ibmvnic.c +++ b/drivers/net/ethernet/ibm/ibmvnic.c @@ -5084,6 +5084,14 @@ static void ibmvnic_tasklet(struct tasklet_struct *t) while (!done) { /* Pull all the valid messages off the CRQ */ while ((crq = ibmvnic_next_crq(adapter)) != NULL) { + /* Ensure that the entire CRQ descriptor queue->msgs + * has been loaded before reading its contents. + * This barrier makes sure ibmvnic_next_crq()'s + * crq->generic.first & IBMVNIC_CRQ_CMD_RSP is loaded + * before ibmvnic_handle_crq()'s + * switch(gen_crq->first) and switch(gen_crq->cmd). + */ + dma_rmb(); ibmvnic_handle_crq(crq, adapter); crq->generic.first = 0; }