Re: [PATCH net-next] net: dsa: mark parsed interface mode for legacy switch drivers

[Vladimir Oltean <olteanv@gmail.com>]

Hi Russell,

On Tue, Aug 08, 2023 at 12:12:16PM +0100, Russell King (Oracle) wrote:
> If we successfully parsed an interface mode with a legacy switch
> driver, populate that mode into phylink's supported interfaces rather
> than defaulting to the internal and gmii interfaces.
> 
> This hasn't caused an issue so far, because when the interface doesn't
> match a supported one, phylink_validate() doesn't clear the supported
> mask, but instead returns -EINVAL. phylink_parse_fixedlink() doesn't
> check this return value, and merely relies on the supported ethtool
> link modes mask being cleared. Therefore, the fixed link settings end
> up being allowed despite validation failing.
> 
> Before this causes a problem, arrange for DSA to more accurately
> populate phylink's supported interfaces mask so validation can
> correctly succeed.
> 
> Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
> ---

How did you notice this? Is there any unconverted DSA switch which has a
phy-mode which isn't PHY_INTERFACE_MODE_INTERNAL or PHY_INTERFACE_MODE_NA?