From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stephen Hemminger Subject: Re: [PATCH v3 0/2] support MAC changes when no live changes allowed Date: Fri, 24 Aug 2018 07:46:27 -0700 Message-ID: <20180824074627.3415e05b@xeon-e3> References: <1535120736-785-1-git-send-email-alejandro.lucero@netronome.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Cc: dev@dpdk.org, stable@dpdk.org, ferruh.yigit@intel.com To: Alejandro Lucero Return-path: Received: from mail-pl1-f194.google.com (mail-pl1-f194.google.com [209.85.214.194]) by dpdk.org (Postfix) with ESMTP id 73B465F17 for ; Fri, 24 Aug 2018 16:46:30 +0200 (CEST) Received: by mail-pl1-f194.google.com with SMTP id d9-v6so1194038plr.2 for ; Fri, 24 Aug 2018 07:46:30 -0700 (PDT) In-Reply-To: <1535120736-785-1-git-send-email-alejandro.lucero@netronome.com> List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" On Fri, 24 Aug 2018 15:25:34 +0100 Alejandro Lucero wrote: > The original patch assumes all NICs can safely change or set the MAC > in any case. However, this is not always true. NFP depends on the firmware > capabilities and this is not always supported. There are other NICs with > this same limitation, although, as far as I know, not in DPDK. Linux kernel > has a IFF_LIVE_ADDR_CHANGE flag and two NICs are checking this flag for > allowing or not live MAC changes The semantic in Linux is different than what I think you are trying to do. Some devices can not change MAC address at all because of hardware or hypervisor restrictions. Other devices can not change address while device is up (started in DPDK API). With Linux the policy was to assume by default device could change address while up. And then let a few virtual devices allow it.