1 files changed, 22 insertions, 2 deletions

diff --git a/drivers/net/phy/mdio_bus.c b/drivers/net/phy/mdio_bus.c
index bd4e8d72dc08..49252d390903 100644
--- a/drivers/net/phy/mdio_bus.c
+++ b/drivers/net/phy/mdio_bus.c
@@ -303,8 +303,18 @@ static int mdio_bus_suspend(struct device * dev, pm_message_t state)
         struct phy_driver *phydrv = to_phy_driver(dev->driver);
         struct phy_device *phydev = to_phy_device(dev);
 
+        /*
+         * We must stop the state machine manually, otherwise it stops out of
+         * control, possibly with the phydev->lock held. Upon resume, netdev
+         * may call phy routines that try to grab the same lock, and that may
+         * lead to a deadlock.
+         */
+        if (phydev->attached_dev)
+                phy_stop_machine(phydev);
+
         if (!mdio_bus_phy_may_suspend(phydev))
                 return 0;
+
         return phydrv->suspend(phydev);
 }
 
@@ -312,10 +322,20 @@ static int mdio_bus_resume(struct device * dev)
 {
         struct phy_driver *phydrv = to_phy_driver(dev->driver);
         struct phy_device *phydev = to_phy_device(dev);
+        int ret;
 
         if (!mdio_bus_phy_may_suspend(phydev))
-                return 0;
-        return phydrv->resume(phydev);
+                goto no_resume;
+
+        ret = phydrv->resume(phydev);
+        if (ret < 0)
+                return ret;
+
+no_resume:
+        if (phydev->attached_dev)
+                phy_start_machine(phydev, NULL);
+
+        return 0;
 }
 
 struct bus_type mdio_bus_type = {