From patchwork Thu Jun 18 15:43:46 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Thomas Falcon X-Patchwork-Id: 217590 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=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, 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 B80B2C433E1 for ; Thu, 18 Jun 2020 15:44:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 94CFA2070A for ; Thu, 18 Jun 2020 15:44:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731704AbgFRPoE (ORCPT ); Thu, 18 Jun 2020 11:44:04 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:49704 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1730208AbgFRPoC (ORCPT ); Thu, 18 Jun 2020 11:44:02 -0400 Received: from pps.filterd (m0098413.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 05IFWYKr093995; Thu, 18 Jun 2020 11:43:53 -0400 Received: from ppma01wdc.us.ibm.com (fd.55.37a9.ip4.static.sl-reverse.com [169.55.85.253]) by mx0b-001b2d01.pphosted.com with ESMTP id 31r2vnqwgw-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 18 Jun 2020 11:43:53 -0400 Received: from pps.filterd (ppma01wdc.us.ibm.com [127.0.0.1]) by ppma01wdc.us.ibm.com (8.16.0.42/8.16.0.42) with SMTP id 05IFdbiQ028770; Thu, 18 Jun 2020 15:43:53 GMT Received: from b03cxnp08026.gho.boulder.ibm.com (b03cxnp08026.gho.boulder.ibm.com [9.17.130.18]) by ppma01wdc.us.ibm.com with ESMTP id 31q6bdcr1m-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 18 Jun 2020 15:43:53 +0000 Received: from b03ledav003.gho.boulder.ibm.com (b03ledav003.gho.boulder.ibm.com [9.17.130.234]) by b03cxnp08026.gho.boulder.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 05IFhniH31392078 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 18 Jun 2020 15:43:49 GMT Received: from b03ledav003.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 8F9366A047; Thu, 18 Jun 2020 15:43:51 +0000 (GMT) Received: from b03ledav003.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id B93706A051; Thu, 18 Jun 2020 15:43:50 +0000 (GMT) Received: from oc7186267434.ibm.com (unknown [9.160.31.222]) by b03ledav003.gho.boulder.ibm.com (Postfix) with ESMTP; Thu, 18 Jun 2020 15:43:50 +0000 (GMT) From: Thomas Falcon To: netdev@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org, Thomas Falcon Subject: [PATCH net] ibmveth: Fix max MTU limit Date: Thu, 18 Jun 2020 10:43:46 -0500 Message-Id: <1592495026-27202-1-git-send-email-tlfalcon@linux.ibm.com> X-Mailer: git-send-email 1.8.3.1 X-TM-AS-GCONF: 00 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.216, 18.0.687 definitions=2020-06-18_13:2020-06-18,2020-06-18 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 bulkscore=0 spamscore=0 phishscore=0 impostorscore=0 malwarescore=0 adultscore=0 clxscore=1015 mlxscore=0 mlxlogscore=901 cotscore=-2147483648 priorityscore=1501 suspectscore=1 lowpriorityscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2004280000 definitions=main-2006180115 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org The max MTU limit defined for ibmveth is not accounting for virtual ethernet buffer overhead, which is twenty-two additional bytes set aside for the ethernet header and eight additional bytes of an opaque handle reserved for use by the hypervisor. Update the max MTU to reflect this overhead. Signed-off-by: Thomas Falcon --- drivers/net/ethernet/ibm/ibmveth.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/ethernet/ibm/ibmveth.c b/drivers/net/ethernet/ibm/ibmveth.c index 96d36ae5049e..c5c732601e35 100644 --- a/drivers/net/ethernet/ibm/ibmveth.c +++ b/drivers/net/ethernet/ibm/ibmveth.c @@ -1715,7 +1715,7 @@ static int ibmveth_probe(struct vio_dev *dev, const struct vio_device_id *id) } netdev->min_mtu = IBMVETH_MIN_MTU; - netdev->max_mtu = ETH_MAX_MTU; + netdev->max_mtu = ETH_MAX_MTU - IBMVETH_BUFF_OH; memcpy(netdev->dev_addr, mac_addr_p, ETH_ALEN);