[{"id":1761982,"web_url":"http://patchwork.ozlabs.org/comment/1761982/","msgid":"<20170901141639.2f77d60f@xeon-e3>","list_archive_url":null,"date":"2017-09-01T21:16:39","subject":"Re: [PATCH iproute2 0/2] fix \"ip link show dev ...\" for NICs with\n\tmany VFs","submitter":{"id":21389,"url":"http://patchwork.ozlabs.org/api/people/21389/","name":"Stephen Hemminger","email":"stephen@networkplumber.org"},"content":"On Fri, 1 Sep 2017 18:39:06 +0200 (CEST)\nMichal Kubecek wrote:\n\n> Two of our customers recently encountered problems with processing of large\n> messages produced by kernel in response to \"ip link show\" for NICs with\n> many (120-128) virtual functions. While some of them have been already\n> addressed in recent versions of iproute2, some still persist.\n> \n> Patch 1 adds check to handle the case when a message fits into the\n> buffer in rtnl_talk() but not into the buffer in iplink_get().\n> \n> Patch 2 increases the buffer size in iplink_get() to suffice even for\n> NICs with 128 VFs. \n> \n> Note: after applying patch 2, patch 1 seems useless as both buffers have\n> the same size so that the check cannot actually trigger. However, as we\n> cannot guarantee they will always stay the same, I believe the check\n> should still be added.\n> \n> Michal Kubecek (2):\n> iplink: check for message truncation in iplink_get()\n> iplink: double the buffer size also in iplink_get()\n> \n> ip/iplink.c | 7 ++++++-\n> 1 file changed, 6 insertions(+), 1 deletion(-)\n> \n\nLooks like the best set of solutions to the kernel side API issue.\nApplied, thanks Michal.","headers":{"Return-Path":"","X-Original-To":"patchwork-incoming@ozlabs.org","Delivered-To":"patchwork-incoming@ozlabs.org","Authentication-Results":["ozlabs.org;\n\tspf=none (mailfrom) smtp.mailfrom=vger.kernel.org\n\t(client-ip=209.132.180.67; helo=vger.kernel.org;\n\tenvelope-from=netdev-owner@vger.kernel.org;\n\treceiver=)","ozlabs.org; dkim=pass (2048-bit key;\n\tunprotected) header.d=networkplumber-org.20150623.gappssmtp.com\n\theader.i=@networkplumber-org.20150623.gappssmtp.com\n\theader.b=\"Q7/2AXey\"; dkim-atps=neutral"],"Received":["from vger.kernel.org (vger.kernel.org [209.132.180.67])\n\tby ozlabs.org (Postfix) with ESMTP id 3xkXB11WR0z9sPk\n\tfor ;\n\tSat, 2 Sep 2017 07:16:57 +1000 (AEST)","(majordomo@vger.kernel.org) by vger.kernel.org via listexpand\n\tid S1752557AbdIAVQn (ORCPT );\n\tFri, 1 Sep 2017 17:16:43 -0400","from mail-pf0-f173.google.com ([209.85.192.173]:33360 \"EHLO\n\tmail-pf0-f173.google.com\" rhost-flags-OK-OK-OK-OK) by vger.kernel.org\n\twith ESMTP id S1752392AbdIAVQl (ORCPT\n\t); Fri, 1 Sep 2017 17:16:41 -0400","by mail-pf0-f173.google.com with SMTP id n73so3692913pfj.0\n\tfor ; Fri, 01 Sep 2017 14:16:41 -0700 (PDT)","from xeon-e3 (76-14-207-240.or.wavecable.com. 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