Re: [PATCH net] net: phy: fix save wrong speed and duplex problem if autoneg is on

From: Jakub Kicinski
Date: Fri Feb 26 2021 - 18:57:03 EST


On Fri, 26 Feb 2021 15:44:42 +0800 Huazhong Tan wrote:
> From: Guangbin Huang <huangguangbin2@xxxxxxxxxx>
>
> 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?