From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751924AbdHaREJ (ORCPT ); Thu, 31 Aug 2017 13:04:09 -0400 Received: from mail-wm0-f48.google.com ([74.125.82.48]:35750 "EHLO mail-wm0-f48.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750813AbdHaREH (ORCPT ); Thu, 31 Aug 2017 13:04:07 -0400 X-Google-Smtp-Source: ADKCNb7aC0HRG/KYCsYujVm7k6g1/RLy7PJVXSTf1ElEt/3IBr7vPe3kYmNsXybbGhl41TbL2xzC1w== Message-ID: <1504199044.22080.11.camel@arista.com> Subject: virtio_net: ethtool supported link modes From: Radu Rendec To: virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Cc: "Michael S. Tsirkin" , Jason Wang Date: Thu, 31 Aug 2017 18:04:04 +0100 Organization: Arista Networks Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.22.6 (3.22.6-2.fc25) Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, Looking at the code in virtnet_set_link_ksettings, it seems the speed and duplex can be set to any valid value. The driver will "remember" them and report them back in virtnet_get_link_ksettings. However, the supported link modes (link_modes.supported in struct ethtool_link_ksettings) is always 0, indicating that no speed/duplex setting is supported. Does it make more sense to set (at least a few of) the supported link modes, such as 10baseT_Half ... 10000baseT_Full? I would expect to see consistency between what is reported in link_modes.supported and what can actually be set. Could you please share your opinion on this? Thank you, Radu Rendec