[PATCH net v2 1/2] net: phy: honor eee_disabled_modes in phy_support_eee()

[Nicolai Buchwitz]

phy_support_eee() copies supported_eee into advertising_eee
unconditionally, overwriting any filtering applied during phy_probe()
based on DT eee-broken-* properties or driver-populated
eee_disabled_modes. MAC drivers that call phy_support_eee() after
probe (e.g. bcmgenet, fec, lan743x, lan78xx, r8169) then cause the PHY
to advertise EEE for modes the user marked as broken.

The symptom is that ethtool --show-eee on the local interface reports
"not supported" (supported & ~eee_disabled_modes is empty) while the
link partner sees EEE negotiated and active.

phy_probe() already filters advertising_eee via eee_disabled_modes
after calling of_set_phy_eee_broken(). Apply the same mask in
phy_support_eee() so the filtering survives the copy.

Fixes: 49168d1980e2 ("net: phy: Add phy_support_eee() indicating MAC support EEE")
Signed-off-by: Nicolai Buchwitz <nb@xxxxxxxxxxx>
---
 drivers/net/phy/phy_device.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c
index c2cdf1ae354249c033445f2d942e07220205b41c..83b074bc4a8f716b3e10c8ff57aff7c7abba0236 100644
--- a/drivers/net/phy/phy_device.c
+++ b/drivers/net/phy/phy_device.c
@@ -2903,7 +2903,8 @@ EXPORT_SYMBOL_GPL(phy_advertise_eee_all);
  */
 void phy_support_eee(struct phy_device *phydev)
 {
-	linkmode_copy(phydev->advertising_eee, phydev->supported_eee);
+	linkmode_andnot(phydev->advertising_eee, phydev->supported_eee,
+			phydev->eee_disabled_modes);
 	phydev->eee_cfg.tx_lpi_enabled = true;
 	phydev->eee_cfg.eee_enabled = true;
 

-- 
2.51.0