lan743x: fix deadlock in lan743x_phy_link_status_change()

Usage of phy_ethtool_get_link_ksettings() in the link status change
handler isn't needed, and in combination with the referenced change
it results in a deadlock. Simply remove the call and replace it with
direct access to phydev->speed. The duplex argument of
lan743x_phy_update_flowcontrol() isn't used and can be removed.

Fixes: c10a485c3de5 ("phy: phy_ethtool_ksettings_get: Lock the phy for consistency")
Reported-by: Alessandro B Maurici <abmaurici@gmail.com>
Tested-by: Alessandro B Maurici <abmaurici@gmail.com>
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Link: https://lore.kernel.org/r/40e27f76-0ba3-dcef-ee32-a78b9df38b0f@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/drivers/net/ethernet/microchip/lan743x_main.c b/drivers/net/ethernet/microchip/lan743x_main.c
index 4fc9782..7d76474 100644 (file)
--- a/drivers/net/ethernet/microchip/lan743x_main.c
+++ b/drivers/net/ethernet/microchip/lan743x_main.c
@@ -914,8 +914,7 @@ static int lan743x_phy_reset(struct lan743x_adapter *adapter)
 }
 
 static void lan743x_phy_update_flowcontrol(struct lan743x_adapter *adapter,
-                                          u8 duplex, u16 local_adv,
-                                          u16 remote_adv)
+                                          u16 local_adv, u16 remote_adv)
 {
        struct lan743x_phy *phy = &adapter->phy;
        u8 cap;
@@ -943,7 +942,6 @@ static void lan743x_phy_link_status_change(struct net_device *netdev)
 
        phy_print_status(phydev);
        if (phydev->state == PHY_RUNNING) {
-               struct ethtool_link_ksettings ksettings;
                int remote_advertisement = 0;
                int local_advertisement = 0;
 
@@ -980,18 +978,14 @@ static void lan743x_phy_link_status_change(struct net_device *netdev)
                }
                lan743x_csr_write(adapter, MAC_CR, data);
 
-               memset(&ksettings, 0, sizeof(ksettings));
-               phy_ethtool_get_link_ksettings(netdev, &ksettings);
                local_advertisement =
                        linkmode_adv_to_mii_adv_t(phydev->advertising);
                remote_advertisement =
                        linkmode_adv_to_mii_adv_t(phydev->lp_advertising);
 
-               lan743x_phy_update_flowcontrol(adapter,
-                                              ksettings.base.duplex,
-                                              local_advertisement,
+               lan743x_phy_update_flowcontrol(adapter, local_advertisement,
                                               remote_advertisement);
-               lan743x_ptp_update_latency(adapter, ksettings.base.speed);
+               lan743x_ptp_update_latency(adapter, phydev->speed);
        }
 }