Re: [PATCH net-next 3/3] net: hns3: add support for link diagnosis info in debugfs

[huangguangbin (A)]

On 2021/7/5 3:57, Andrew Lunn wrote:
> > > > Hi Jakub, I have a question to consult you.
> > > > Some fault information in our patch are not existed in current ethtool extended
> > > > link states, for examples:
> > > > "Serdes reference clock lost"
> > > > "Serdes analog loss of signal"
> > > > "SFP tx is disabled"
> > > > "PHY power down"
> > >
> > > Why would the PHY be powered down if user requested port to be up?
> > In the case of other user may use MDIO tool to write PHY register directly to make
> > PHY power down, if link state can display this information, I think it is helpful.
>
> If the user directly writes to PHY registers, they should expect bad
> things to happen. They can do a lot more than power the PHY down. They
> could configure it into loopback mode, turn off autoneg and force a
> mode which is compatible with the peer, etc.
>
> I don't think you need to tell the user they have pointed a foot gun
> at their feet and pulled the trigger.
>
>     Andrew
> .
OK, I accept your point, thanks!