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Subject: Re: [PATCH net] net: phy: fix save wrong speed and duplex problem if
 autoneg is on
To:     Jakub Kicinski <kuba@kernel.org>
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>
References: <1614325482-25208-1-git-send-email-tanhuazhong@huawei.com>
 <20210226155603.6a1cda0b@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com>
From:   Huazhong Tan <tanhuazhong@huawei.com>
Message-ID: <cb001681-137d-3352-b334-63d1a80cae36@huawei.com>
Date:   Sat, 27 Feb 2021 09:27:35 +0800
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On 2021/2/27 7:56, Jakub Kicinski wrote:
> 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?
will add a fixes tag in V2, thanks.
> .