From mboxrd@z Thu Jan 1 00:00:00 1970 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=-0.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no 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 C9400C282DD for ; Thu, 9 Jan 2020 16:19:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 91C4320661 for ; Thu, 9 Jan 2020 16:19:17 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=networkplumber-org.20150623.gappssmtp.com header.i=@networkplumber-org.20150623.gappssmtp.com header.b="U8HbGedl" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1733067AbgAIQTR (ORCPT ); Thu, 9 Jan 2020 11:19:17 -0500 Received: from mail-pl1-f193.google.com ([209.85.214.193]:43010 "EHLO mail-pl1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729722AbgAIQTQ (ORCPT ); Thu, 9 Jan 2020 11:19:16 -0500 Received: by mail-pl1-f193.google.com with SMTP id p27so2738546pli.10 for ; Thu, 09 Jan 2020 08:19:16 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=networkplumber-org.20150623.gappssmtp.com; s=20150623; h=date:from:to:cc:subject:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=fvXjjGfX/0aEoaa+z96ocToPdOyz4XVCqqYcAqf7xY8=; b=U8HbGedleEZxd8pBvzlhQudi8nGy6k+yAIwWVawzrT9KXxyQmj85iOyDbSueBg2bi8 dbIMSi9oZ61AOxKZXak6cL0k6iJFZ3z7JbfF8pTjOPcTEp/3+Ily0lyUPCFfEsrCMbcK jYYMG56vRgeEHTQPqwV2IWdtdXQnL5l9/gpNoGbJZ22cBaDYxOqUkVyDjNirti3Xatnq TTsHrB4VovbCgJ/hcdpP5B2Wc6olLve2X0j6a0Nx9dYY3BylTrXva5mx5+cEnSLsHz+W gnZlkBHgNaKEK4/SEA9QapdTjhiPlqfRx4dPKni2eze66k7dUVEf0XpnYrvK2FI1OoQP EM1w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=fvXjjGfX/0aEoaa+z96ocToPdOyz4XVCqqYcAqf7xY8=; b=l+dFdDPxyaJIgbTaV8ZDk+svglOF+XYBNyhTLQuF1ga6bwVUNH0j6b6PcYBpJWDuY7 gYcHsFAmiQ2444eZDQGqGReROuSa38ESHb86urzphTrVeSI/4Suzvjb0yqbybgakKqeA vwQyDzURjroLCR/tILAzVKkNJxnkLSHgiz4d4OTs45GbTR5XZutgXU7BFZtDAJmav7aa 2sKQ6tMSb9oEt1l+ucH1WdKCfmtnh9loaeKujtNeGbNvXrrxHrn2WPoK9Va2MVTT5rUP zi2kmv4sqKKQk//pr39Rjz7ZTZQvGY5i5N/rV+FJzhGqgRufDPLWYLi5u9aEeC9ZQlCH afsg== X-Gm-Message-State: APjAAAULNj0PB2a6k1Lup6OQtyLV/ydjhaXMjbHkWULqBVpQrdDDWXc6 fFjYuFbXDjwF0y+2fO/bgkInBQ== X-Google-Smtp-Source: APXvYqzNNDhp6g7WvuAaM9xpP0y6XC4pB4Rs3KBf6REubmvhIR+wffAL55NEmJVFZdXetgj2Pg0GRg== X-Received: by 2002:a17:902:b498:: with SMTP id y24mr11984010plr.97.1578586755478; Thu, 09 Jan 2020 08:19:15 -0800 (PST) Received: from hermes.lan (204-195-22-127.wavecable.com. [204.195.22.127]) by smtp.gmail.com with ESMTPSA id u26sm7910317pfn.46.2020.01.09.08.19.14 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 09 Jan 2020 08:19:15 -0800 (PST) Date: Thu, 9 Jan 2020 08:19:07 -0800 From: Stephen Hemminger To: Horatiu Vultur Cc: , , , , , , , , , , , , , , Subject: Re: [RFC net-next Patch 0/3] net: bridge: mrp: Add support for Media Redundancy Protocol(MRP) Message-ID: <20200109081907.06281c0f@hermes.lan> In-Reply-To: <20200109150640.532-1-horatiu.vultur@microchip.com> References: <20200109150640.532-1-horatiu.vultur@microchip.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Thu, 9 Jan 2020 16:06:37 +0100 Horatiu Vultur wrote: > Media Redundancy Protocol is a data network protocol standardized by > International Electrotechnical Commission as IEC 62439-2. It allows rings of > Ethernet switches to overcome any single failure with recovery time faster than > STP. It is primarily used in Industrial Ethernet applications. > > This is the first proposal of implementing a subset of the standard. It supports > only 2 roles of an MRP node. It supports only Media Redundancy Manager(MRM) and > Media Redundancy Client(MRC). In a MRP ring, each node needs to support MRP and > in a ring can be only one MRM and multiple MRC. It is possible to have multiple > instances of MRP on a single node. But a port can be part of only one MRP > instance. > > The MRM is responsible for detecting when there is a loop in the ring. It is > sending the frame MRP_Test to detect the loops. It would send MRP_Test on both > ports in the ring and if the frame is received at the other end, then the ring > is closed. Meaning that there is a loop. In this case it sets the port state to > BLOCKED, not allowing traffic to pass through except MRP frames. In case it > stops receiving MRP_Test frames from itself then the MRM will detect that the > ring is open, therefor it would notify the other nodes of this change and will > set the state of the port to be FORWARDING. > > The MRC is responsible for forwarding MRP_Test frames between the ring ports > (and not to flood on other ports) and to listen when there is a change in the > network to clear the FDB. > > Similar with STP, MRP is implemented on top of the bridge and they can't be > enable at the same time. While STP runs on all ports of the bridge, MRP needs to > run only on 2 ports. > > The bridge needs to: > - notify when the link of one of the ports goes down or up, because MRP instance > needs to react to link changes by sending MRP_LinkChange frames. > - notify when one of the ports are removed from the bridge or when the bridge > is destroyed, because if the port is part of the MRP ring then MRP state > machine should be stopped. > - add a handler to allow MRP instance to process MRP frames, if MRP is enabled. > This is similar with STP design. > - add logic for MRP frames inside the bridge. The bridge will just detect MRP > frames and it would forward them to the upper layer to allow to process it. > - update the logic to update non-MRP frames. If MRP is enabled, then look also > at the state of the port to decide to forward or not. > > To create a MRP instance on the bridge: > $ bridge mrp add dev br0 p_port eth0 s_port eth1 ring_role 2 ring_id 1 > > Where: > p_port, s_port: can be any port under the bridge > ring_role: can have the value 1(MRC - Media Redundancy Client) or > 2(MRM - Media Redundancy Manager). In a ring can be only one MRM. > ring_id: unique id for each MRP instance. > > It is possible to create multiple instances. Each instance has to have it's own > ring_id and a port can't be part of multiple instances: > $ bridge mrp add dev br0 p_port eth2 s_port eth3 ring_role 1 ring_id 2 > > To see current MRP instances and their status: > $ bridge mrp show > dev br0 p_port eth2 s_port eth3 ring_role 1 ring_id 2 ring_state 3 > dev br0 p_port eth0 s_port eth1 ring_role 2 ring_id 1 ring_state 4 > > If this patch series is well received, the in the future it could be extended > with the following: > - add support for Media Redundancy Automanager. This role allows a node to > detect if needs to behave as a MRM or MRC. The advantage of this role is that > the user doesn't need to configure the nodes each time they are added/removed > from a ring and it adds redundancy to the manager. > - add support for Interconnect rings. This allow to connect multiple rings. > - add HW offloading. The standard defines 4 recovery times (500, 200, 30 and 10 > ms). To be able to achieve 30 and 10 it is required by the HW to generate the > MRP_Test frames and detect when the ring is open/closed. > > Horatiu Vultur (3): > net: bridge: mrp: Add support for Media Redundancy Protocol > net: bridge: mrp: Integrate MRP into the bridge > net: bridge: mrp: Add netlink support to configure MRP > > include/uapi/linux/if_bridge.h | 27 + > include/uapi/linux/if_ether.h | 1 + > include/uapi/linux/rtnetlink.h | 7 + > net/bridge/Kconfig | 12 + > net/bridge/Makefile | 2 + > net/bridge/br.c | 19 + > net/bridge/br_device.c | 3 + > net/bridge/br_forward.c | 1 + > net/bridge/br_if.c | 10 + > net/bridge/br_input.c | 22 + > net/bridge/br_mrp.c | 1517 ++++++++++++++++++++++++++++++++ > net/bridge/br_mrp_timer.c | 227 +++++ > net/bridge/br_netlink.c | 9 + > net/bridge/br_private.h | 30 + > net/bridge/br_private_mrp.h | 208 +++++ > security/selinux/nlmsgtab.c | 5 +- > 16 files changed, 2099 insertions(+), 1 deletion(-) > create mode 100644 net/bridge/br_mrp.c > create mode 100644 net/bridge/br_mrp_timer.c > create mode 100644 net/bridge/br_private_mrp.h > Can this be implemented in userspace? Putting STP in the kernel was a mistake (even original author says so). Adding more control protocols in kernel is a security and stability risk.