From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752907AbcFNQz1 (ORCPT ); Tue, 14 Jun 2016 12:55:27 -0400 Received: from ausc60pc101.us.dell.com ([143.166.85.206]:22549 "EHLO ausc60pc101.us.dell.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752790AbcFNQzY (ORCPT ); Tue, 14 Jun 2016 12:55:24 -0400 DomainKey-Signature: s=smtpout; d=dell.com; c=nofws; q=dns; h=X-LoopCount0:X-IronPort-AV:From:To:CC:Subject: Thread-Topic:Thread-Index:Date:Message-ID:References: In-Reply-To:Accept-Language:Content-Language: X-MS-Has-Attach:X-MS-TNEF-Correlator: x-ms-exchange-transport-fromentityheader:x-originating-ip: Content-Type:Content-Transfer-Encoding:MIME-Version: Return-Path; b=gvt2oA5ZbeaFQhsoIqJy2dKrSZ4kyEgcxcaqJ2njPlYnqXn6rhyNvcL3 mUORD/IzydaNkITgSrKKDUZ4M/oaX/Uu/+evihuqaXJWQU6UtUp1EivXB iZYtG9MU6n+RBZ7npsTxgFtjaYEJgo/mBatrZxLXuXb0hsmu5Ar5nHIRZ c=; X-LoopCount0: from 10.170.28.40 X-IronPort-AV: E=Sophos;i="5.26,471,1459832400"; d="scan'208";a="945216560" From: To: , CC: , , , , , , Subject: RE: [PATCH v6] r8152: Add support for setting pass through MAC address on RTL8153-AD Thread-Topic: [PATCH v6] r8152: Add support for setting pass through MAC address on RTL8153-AD Thread-Index: AQHRwOmaCsYXCAkS0k2cIAYu9FvIC5/kHLcAgACkH4CAACJkAIAEoj4AgAADY4CAAAILAP//rGRA Date: Tue, 14 Jun 2016 16:55:21 +0000 Message-ID: References: <1465323757-7249-1-git-send-email-mario_limonciello@dell.com> <201606141828.10969@pali> <20160614164017.GB14477@kroah.com> <201606141847.36109@pali> In-Reply-To: <201606141847.36109@pali> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-ms-exchange-transport-fromentityheader: Hosted x-originating-ip: [10.208.89.195] Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from base64 to 8bit by mail.home.local id u5EGtXdi018330 > -----Original Message----- > From: Pali Rohár [mailto:pali.rohar@gmail.com] > Sent: Tuesday, June 14, 2016 11:48 AM > To: Greg KH > Cc: David Miller ; andrew@lunn.ch; Limonciello, > Mario ; hayeswang@realtek.com; linux- > kernel@vger.kernel.org; netdev@vger.kernel.org; linux- > usb@vger.kernel.org; anthony.wong@canonical.com > Subject: Re: [PATCH v6] r8152: Add support for setting pass through MAC > address on RTL8153-AD > > On Tuesday 14 June 2016 18:40:17 Greg KH wrote: > > On Tue, Jun 14, 2016 at 06:28:10PM +0200, Pali Rohár wrote: > > > On Saturday 11 June 2016 19:42:26 David Miller wrote: > > > > From: Andrew Lunn > > > > Date: Sat, 11 Jun 2016 17:39:21 +0200 > > > > > > > > > What is still open is do we want to accept it at all? Do we > > > > > accept the concept of putting the same MAC address on multiple > > > > > interfaces at hotplug time? Do we trust BIOS vendors to not > > > > > keep changing DSDT property name, since it is not > > > > > standardised? > > > > > > > > > > Do we want this at all should be decided by somebody more > > > > > senior then those passing comments on the code. > > > > > > > > Indeed, I think the behavior of using the same MAC address on > > > > multiple interfaces if we plug several of these in at once is not > > > > good. > > > > > > > > We shouldn't behave this way just because the Microsoft driver > > > > does. > > > > > > I agree, but in some cases it is night mare for local admins when > > > booting different OS cause changing MAC address on local network. > > > > > > Another similar situation: Imagine that you have two USB network > > > cards and both have "burned" into their registers same MAC > > > address. If you connect both those USB network cards, linux kernel > > > bind appropriate driver which read MAC address for both those > > > cards. But those addresses are same. What will linux kernel do in > > > this case? > > > > If you can find such a broken USB device, try it and see :) > > What do you mean by broken USB device? > > You have never seen two ethernet cards with same MAC addresses? Right I > have not seen two USB, but there is non zero chance that could happen. > Specially now when more and more people starts using USB network cards. > > > (hint, might be hard to find, I've never seen such a device before.) > > > > I don't see how that pertains to this issue, sorry, how does broken > > USB hardware compare to a working Dell device? > > It is same, how to handle two network cards which tell us, that they > have same MAC addresses. > The kernel handles this just fine. In doing this patch I checked to see what it does in that scenario. Two devices are made. systemd doesn't rename the second device via the MAC name (eg enxAABBCCDDEEFF).