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=-5.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=ham 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 3839EC3A5A9 for ; Mon, 4 May 2020 13:29:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1ACAF2075B for ; Mon, 4 May 2020 13:29:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728240AbgEDN3w (ORCPT ); Mon, 4 May 2020 09:29:52 -0400 Received: from mx2.suse.de ([195.135.220.15]:33040 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726404AbgEDN3w (ORCPT ); Mon, 4 May 2020 09:29:52 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id 16598AD2C; Mon, 4 May 2020 13:29:51 +0000 (UTC) Received: by lion.mk-sys.cz (Postfix, from userid 1000) id E7EB7604EE; Mon, 4 May 2020 15:29:47 +0200 (CEST) Date: Mon, 4 May 2020 15:29:47 +0200 From: Michal Kubecek To: netdev@vger.kernel.org Cc: Oleksij Rempel , Marek Vasut , Andrew Lunn , Florian Fainelli , Jonathan Corbet , linux-kernel@vger.kernel.org, Russell King , mkl@pengutronix.de, kernel@pengutronix.de, David Jander , Jakub Kicinski , Christian Herber , "David S. Miller" , Heiner Kallweit Subject: Re: [PATCH v5 1/2] ethtool: provide UAPI for PHY master/slave configuration. Message-ID: <20200504132947.GB8237@lion.mk-sys.cz> References: <20200504071214.5890-1-o.rempel@pengutronix.de> <20200504071214.5890-2-o.rempel@pengutronix.de> <20200504091044.GA8237@lion.mk-sys.cz> <20200504101029.zt3eu7jsywdiq4tu@pengutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200504101029.zt3eu7jsywdiq4tu@pengutronix.de> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, May 04, 2020 at 12:10:29PM +0200, Oleksij Rempel wrote: > > > diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c > > > index ac2784192472f..42dda9d2082ee 100644 > > > --- a/drivers/net/phy/phy_device.c > > > +++ b/drivers/net/phy/phy_device.c > > > @@ -1768,6 +1768,90 @@ int genphy_setup_forced(struct phy_device *phydev) > > > } > > > EXPORT_SYMBOL(genphy_setup_forced); > > > > > > +static int genphy_setup_master_slave(struct phy_device *phydev) > > > +{ > > > + u16 ctl = 0; > > > + > > > + if (!phydev->is_gigabit_capable) > > > + return 0; > > > > Why did you revert to silently ignoring requests in this case? > > genphy_setup_forced() is called by __genphy_config_aneg() and this can > be called by a PHY driver after configuring master slave mode locally by > PHY driver. See tja11xx patch. Same can be potentially done in the phy/realtek.c > driver. > > Currently my imagination is not caffeanized enough to > provide a better solution. Do you have ideas? If we have the check in ethnl_update_linkmodes(), we shouldn't really get here so I believe we can leave this part as it is. > > > static int ethnl_update_linkmodes(struct genl_info *info, struct nlattr **tb, > > > struct ethtool_link_ksettings *ksettings, > > > bool *mod) > > > { > > > struct ethtool_link_settings *lsettings = &ksettings->base; > > > bool req_speed, req_duplex; > > > + const struct nlattr *master_slave_cfg; > > > int ret; > > > > > > + master_slave_cfg = tb[ETHTOOL_A_LINKMODES_MASTER_SLAVE_CFG]; > > > + if (master_slave_cfg) { > > > + u8 cfg = nla_get_u8(master_slave_cfg); > > > + if (!ethnl_validate_master_slave_cfg(cfg)) { > > > + GENL_SET_ERR_MSG(info, "LINKMODES_MASTER_SLAVE_CFG contains not valid value"); > > > + return -EOPNOTSUPP; > > > + } > > > + } > > > > Please set also the "bad attribute" in extack, it may help > > non-interactive clients. > > > > Also, it would be nice to report error if client wants to set master/slave but > > driver does not support it. How about this? > > > > if (master_slave_cfg) { > > u8 cfg = nla_get_u8(master_slave_cfg); > > > > if (lsettings->master_slave_cfg == MASTER_SLAVE_CFG_UNSUPPORTED) { > > NL_SET_ERR_MSG_ATTR(info->extack, master_slave_cfg, > > "master/slave configuration not supported by device"); > > return -EOPNOTSUPP; > > } > > if (!ethnl_validate_master_slave_cfg(cfg)) { > > NL_SET_ERR_MSG_ATTR(info->extack, master_slave_cfg, > > "master/slave value is invalid"); > > return -EOPNOTSUPP; > > } > > } > > > > looks good. thx! > > > > > Do you plan to allow handling master/slave also via ioctl()? > > no. > > > If yes, we should > > also add the sanity checks to ioctl code path. If not, we should prevent > > passing non-zero values from userspace to driver. > > What is the best place to add this sanity check? If there is no plan to allow handling master/slave via ioctl, the best option would IMHO be zeroing both fields in ethtool_get_link_ksettings() right before the call to store_link_ksettings_for_user() and either zeroing master_slave_cfg in ethtool_set_link_ksettings() after the call load_link_ksettings_from_user(), or checking that it's zero (i.e. that userspace left it untouched). Michal