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Date:   Fri, 26 Feb 2021 15:56:03 -0800
From:   Jakub Kicinski <kuba@kernel.org>
To:     Huazhong Tan <tanhuazhong@huawei.com>
Cc:     <andrew@lunn.ch>, <f.fainelli@gmail.com>, <hkallweit1@gmail.com>,
        <davem@davemloft.net>, <netdev@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>,
        Guangbin Huang <huangguangbin2@huawei.com>
Subject: Re: [PATCH net] net: phy: fix save wrong speed and duplex problem
 if autoneg is on
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On Fri, 26 Feb 2021 15:44:42 +0800 Huazhong Tan wrote:
> From: Guangbin Huang <huangguangbin2@huawei.com>
> 
> If phy uses generic driver and autoneg is on, enter command
> "ethtool -s eth0 speed 50" will not change phy speed actually, but
> command "ethtool eth0" shows speed is 50Mb/s because phydev->speed
> has been set to 50 and no update later.
> 
> And duplex setting has same problem too.
> 
> However, if autoneg is on, phy only changes speed and duplex according to
> phydev->advertising, but not phydev->speed and phydev->duplex. So in this
> case, phydev->speed and phydev->duplex don't need to be set in function
> phy_ethtool_ksettings_set() if autoneg is on.

Can we get a Fixes tag for this one? How far back does this behavior
date?