Re: [PATCH iwl-net 6/10] ice: check PHY autoneg capability before rejecting ethtool autoneg setting

[Tony Nguyen <anthony.l.nguyen@intel.com>]

On 4/2/2026 10:40 PM, Aleksandr Loktionov wrote:
> ice_set_link_ksettings() rejects autoneg requests by comparing
> user settings against safe_ks which is populated by
> ice_phy_type_to_ethtool(). The Autoneg bit in safe_ks is set
> only if the current PHY configuration reports it supported,
> but this misses PHYs that support autoneg and have it available
> through PHY capabilities. Pull the autoneg flag from the actual
> PHY capabilities (already fetched earlier in the function) to
> ensure the user can toggle autoneg on any capable PHY.
> 
> Fixes: 5cd349c349d6 ("ice: report supported and advertised autoneg using PHY capabilities")
> Cc: stable@vger.kernel.org
> Signed-off-by: Jan Glaza <jan.glaza@intel.com>
> Signed-off-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com>
> ---
>   drivers/net/ethernet/intel/ice/ice_ethtool.c | 8 ++++++++
>   1 file changed, 8 insertions(+)
> 
> diff --git a/drivers/net/ethernet/intel/ice/ice_ethtool.c b/drivers/net/ethernet/intel/ice/ice_ethtool.c
> index 49b9376..44483bc 100644
> --- a/drivers/net/ethernet/intel/ice/ice_ethtool.c
> +++ b/drivers/net/ethernet/intel/ice/ice_ethtool.c
> @@ -2654,6 +2654,14 @@ ice_set_link_ksettings(struct net_device *netdev,
>   	/* Get link modes supported by hardware.*/
>   	ice_phy_type_to_ethtool(netdev, &safe_ks);
>   
> +	/* Pull the value of autoneg from phy caps to ensure we allow
> +	 * toggling it on all PHYs that support it.
> +	 */
> +	if (ice_is_phy_caps_an_enabled(phy_caps)) {
> +		ethtool_link_ksettings_add_link_mode(&safe_ks, supported, Autoneg);
> +		set_bit(ETHTOOL_LINK_MODE_FEC_NONE_BIT, safe_ks.link_modes.supported);

 From Sashiko:

This isn't a bug, but should this use 
ethtool_link_ksettings_add_link_mode() instead of calling set_bit() 
directly? Using set_bit() on the link modes breaks the ethtool interface 
abstraction.

Also, does this incorrectly couple the ETHTOOL_LINK_MODE_FEC_NONE_BIT 
support with Autonegotiation support? Forward Error Correction support 
is independent of Autonegotiation.

For PHYs lacking Autonegotiation, the FEC none bit will not be added to 
safe_ks.link_modes.supported. When a user requests settings via ethtool, 
copy_ks.link_modes.advertising will likely contain the FEC none bit 
since it is unconditionally returned by ice_get_link_ksettings().

> +	}
> +
>   	/* and check against modes requested by user.
>   	 * Return an error if unsupported mode was set.
>   	 */