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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id EA9EEC32772 for ; Sat, 20 Aug 2022 09:16:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S245366AbiHTJQ0 (ORCPT ); Sat, 20 Aug 2022 05:16:26 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35748 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231132AbiHTJQZ (ORCPT ); Sat, 20 Aug 2022 05:16:25 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9B946B4430; Sat, 20 Aug 2022 02:16:23 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 2BC0661037; Sat, 20 Aug 2022 09:16:23 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 36D03C433D6; Sat, 20 Aug 2022 09:16:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1660986982; bh=m8+eVH1apY8yJflD/rlc30nA3D1GDtr+IypyoRcZTHQ=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=Cx/qzT7dcPFJMqYA78q1sbqlh43I/RiBggZORHyTgjuPeRpmgR6sMhPiCI/qsf3j1 +YpZPjsfkYBVpATdp8AoBujE5QefNq9tOWKB4eMRzZmUEuz5hD2reYkZ4s31cX1yzJ fSXfpFg/wmgNayuPOkQjF8ETb4FECy1BM79hboKquuFmuI8zovSyemSCY83kt6IKKV RyNYX4ho+riLPai51wKezOomhYEleNHf2nTLgBALpULatgs45eOQfwzignlKAKlL93 BKfB0EfCPJdKi4lpTeZ8P0YK5sT5musm/j+hETGcG8Oav3MvF2dGFRvldXr/wsaOtc Ph/jZswrRoDjw== Received: by pali.im (Postfix) id 05A395D0; Sat, 20 Aug 2022 11:16:18 +0200 (CEST) Date: Sat, 20 Aug 2022 11:16:18 +0200 From: Pali =?utf-8?B?Um9ow6Fy?= To: Sean Anderson Cc: Michal =?utf-8?B?U3VjaMOhbmVr?= , Stephen Hemminger , Tim Harvey , netdev , u-boot , Device Tree Mailing List Subject: Re: ethernet dt aliases implications in U-Boot and Linux Message-ID: <20220820091618.vdrisqa6twvl23vj@pali> References: <5914cae0-e87b-fb94-85dd-33311fc84c52@seco.com> <20220808210945.GP17705@kitsune.suse.cz> <20220808143835.41b38971@hermes.local> <20220808214522.GQ17705@kitsune.suse.cz> <53f91ad4-a0d1-e223-a173-d2f59524e286@seco.com> <20220809213146.m6a3kfex673pjtgq@pali> <20220809214207.bd4o7yzloi4npzf7@pali> <2083d6d6-eecf-d651-6f4f-87769cd3d60d@seco.com> <20220809224535.ymzzt6a4v756liwj@pali> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20220809224535.ymzzt6a4v756liwj@pali> User-Agent: NeoMutt/20180716 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Wednesday 10 August 2022 00:45:35 Pali Rohár wrote: > On Tuesday 09 August 2022 18:41:25 Sean Anderson wrote: > > On 8/9/22 5:42 PM, Pali Rohár wrote: > > > On Tuesday 09 August 2022 17:36:52 Sean Anderson wrote: > > >> On 8/9/22 5:31 PM, Pali Rohár wrote: > > >> > On Tuesday 09 August 2022 16:48:23 Sean Anderson wrote: > > >> >> On 8/8/22 5:45 PM, Michal Suchánek wrote: > > >> >> > On Mon, Aug 08, 2022 at 02:38:35PM -0700, Stephen Hemminger wrote: > > >> >> >> On Mon, 8 Aug 2022 23:09:45 +0200 > > >> >> >> Michal Suchánek wrote: > > >> >> >> > > >> >> >> > On Mon, Aug 08, 2022 at 03:57:55PM -0400, Sean Anderson wrote: > > >> >> >> > > Hi Tim, > > >> >> >> > > > > >> >> >> > > On 8/8/22 3:18 PM, Tim Harvey wrote: > > >> >> >> > > > Greetings, > > >> >> >> > > > > > >> >> >> > > > I'm trying to understand if there is any implication of 'ethernet' > > >> >> >> > > > aliases in Linux such as: > > >> >> >> > > > aliases { > > >> >> >> > > > ethernet0 = &eqos; > > >> >> >> > > > ethernet1 = &fec; > > >> >> >> > > > ethernet2 = &lan1; > > >> >> >> > > > ethernet3 = &lan2; > > >> >> >> > > > ethernet4 = &lan3; > > >> >> >> > > > ethernet5 = &lan4; > > >> >> >> > > > ethernet6 = &lan5; > > >> >> >> > > > }; > > >> >> >> > > > > > >> >> >> > > > I know U-Boot boards that use device-tree will use these aliases to > > >> >> >> > > > name the devices in U-Boot such that the device with alias 'ethernet0' > > >> >> >> > > > becomes eth0 and alias 'ethernet1' becomes eth1 but for Linux it > > >> >> >> > > > appears that the naming of network devices that are embedded (ie SoC) > > >> >> >> > > > vs enumerated (ie pci/usb) are always based on device registration > > >> >> >> > > > order which for static drivers depends on Makefile linking order and > > >> >> >> > > > has nothing to do with device-tree. > > >> >> >> > > > > > >> >> >> > > > Is there currently any way to control network device naming in Linux > > >> >> >> > > > other than udev? > > >> >> >> > > > > >> >> >> > > You can also use systemd-networkd et al. (but that is the same kind of mechanism) > > >> >> >> > > > > >> >> >> > > > Does Linux use the ethernet aliases for anything at all? > > >> >> >> > > > > >> >> >> > > No :l > > >> >> >> > > > >> >> >> > Maybe it's a great opportunity for porting biosdevname to DT based > > >> >> >> > platforms ;-) > > >> >> >> > > >> >> >> Sorry, biosdevname was wrong way to do things. > > >> >> >> Did you look at the internals, it was dumpster diving as root into BIOS. > > >> >> > > > >> >> > When it's BIOS what defines the names then you have to read them from > > >> >> > the BIOS. Recently it was updated to use some sysfs file or whatver. > > >> >> > It's not like you would use any of that code with DT, anyway. > > >> >> > > > >> >> >> Systemd-networkd does things in much more supportable manner using existing > > >> >> >> sysfs API's. > > >> >> > > > >> >> > Which is a dumpster of systemd code, no thanks. > > >> >> > > > >> >> > I want my device naming independent of the init system, especially if > > >> >> > it's systemd. > > >> >> > > >> >> Well, there's always nameif... > > >> >> > > >> >> That said, I have made [1] for people using systemd-networkd. > > >> >> > > >> >> --Sean > > >> >> > > >> >> [1] https://github.com/systemd/systemd/pull/24265 > > >> > > > >> > Hello! > > >> > > > >> > In some cases "label" DT property can be used also as interface name. > > >> > For example this property is already used by DSA kernel driver. > > >> > > > >> > I created very simple script which renames all interfaces in system to > > >> > their "label" DT property (if there is any defined). > > >> > > > >> > #!/bin/sh > > >> > for iface in `ls /sys/class/net/`; do > > >> > for of_node in of_node device/of_node; do > > >> > if test -e /sys/class/net/$iface/$of_node/; then > > >> > label=`cat /sys/class/net/$iface/$of_node/label 2>/dev/null` > > >> > if test -n "$label" && test "$label" != "$iface"; then > > >> > echo "Renaming net interface $iface to $label..." > > >> > up=$((`cat /sys/class/net/$iface/flags 2>/dev/null || echo 1` & 0x1)) > > >> > if test "$up" != "0"; then > > >> > ip link set dev $iface down > > >> > fi > > >> > ip link set dev $iface name "$label" && iface=$label > > >> > if test "$up" != "0"; then > > >> > ip link set dev $iface up > > >> > fi > > >> > fi > > >> > break > > >> > fi > > >> > done > > >> > done > > >> > > > >> > Maybe it would be better first to use "label" and then use ethernet alias? > > >> > > > >> > > >> It looks like there is already precedent for using ID_NET_LABEL_ONBOARD for > > >> this purpose (on SMBios boards). It should be a fairly simple extension to > > >> add that as well. However, I didn't find any uses of this in Linux or U-Boot > > >> (although I did find plenty of ethernet LEDs). Do you have an example you > > >> could point me to? > > >> > > >> --Sean > > > > > > In linux: > > > $ git grep '"label"' net/dsa/dsa2.c > > > net/dsa/dsa2.c: const char *name = of_get_property(dn, "label", NULL); > > > > > > > Hm, if Linux is using the label, then do we need to rename things in userspace? > > It uses it _only_ for DSA drivers. For all other drivers (e.g. USB or > PCIe based network adapters) it does not use label. Hello Sean! I would like to ask, are you going to use/implement "label" support (so it would work also for non-DSA drivers) in userspace, in similar way how you did aliases? https://github.com/systemd/systemd/pull/24265