From mboxrd@z Thu Jan 1 00:00:00 1970 From: Julian Wiedmann Subject: [PATCH net 1/3] s390/qeth: fix thinko in IPv4 multicast address tracking Date: Fri, 1 Dec 2017 10:14:49 +0100 Message-ID: <20171201091451.52270-2-jwi@linux.vnet.ibm.com> References: <20171201091451.52270-1-jwi@linux.vnet.ibm.com> Cc: , , Martin Schwidefsky , Heiko Carstens , Stefan Raspl , Ursula Braun , Julian Wiedmann To: David Miller Return-path: Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:32774 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751976AbdLAJPG (ORCPT ); Fri, 1 Dec 2017 04:15:06 -0500 Received: from pps.filterd (m0098410.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.21/8.16.0.21) with SMTP id vB19EknA050055 for ; Fri, 1 Dec 2017 04:15:06 -0500 Received: from e06smtp14.uk.ibm.com (e06smtp14.uk.ibm.com [195.75.94.110]) by mx0a-001b2d01.pphosted.com with ESMTP id 2ek49b80gp-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Fri, 01 Dec 2017 04:15:05 -0500 Received: from localhost by e06smtp14.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Fri, 1 Dec 2017 09:15:03 -0000 In-Reply-To: <20171201091451.52270-1-jwi@linux.vnet.ibm.com> Sender: netdev-owner@vger.kernel.org List-ID: Commit 5f78e29ceebf ("qeth: optimize IP handling in rx_mode callback") reworked how secondary addresses are managed for qeth devices. Instead of dropping & subsequently re-adding all addresses on every ndo_set_rx_mode() call, qeth now keeps track of the addresses that are currently registered with the HW. On a ndo_set_rx_mode(), we thus only need to do (de-)registration requests for the addresses that have actually changed. On L3 devices, the lookup for IPv4 Multicast addresses checks the wrong hashtable - and thus never finds a match. As a result, we first delete *all* such addresses, and then re-add them again. So each set_rx_mode() causes a short period where the IPv4 Multicast addresses are not registered, and the card stops forwarding inbound traffic for them. Fix this by setting the ->is_multicast flag on the lookup object, thus enabling qeth_l3_ip_from_hash() to search the correct hashtable and find a match there. Fixes: 5f78e29ceebf ("qeth: optimize IP handling in rx_mode callback") Signed-off-by: Julian Wiedmann --- drivers/s390/net/qeth_l3_main.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/s390/net/qeth_l3_main.c b/drivers/s390/net/qeth_l3_main.c index aadd384316a3..e79936b50698 100644 --- a/drivers/s390/net/qeth_l3_main.c +++ b/drivers/s390/net/qeth_l3_main.c @@ -1376,6 +1376,7 @@ qeth_l3_add_mc_to_hash(struct qeth_card *card, struct in_device *in4_dev) tmp->u.a4.addr = be32_to_cpu(im4->multiaddr); memcpy(tmp->mac, buf, sizeof(tmp->mac)); + tmp->is_multicast = 1; ipm = qeth_l3_ip_from_hash(card, tmp); if (ipm) { -- 2.13.5