net: stmmac: Avoid deadlock on suspend/resume

The stmmac driver will try to acquire its private mutex during suspend
via phylink_resolve() -> stmmac_mac_link_down() -> stmmac_eee_init().
However, the phylink configuration is updated with the private mutex
held already, which causes a deadlock during suspend.

Fix this by moving the phylink configuration updates out of the region
of code protected by the private mutex.

Fixes: 19e13cb27b ("net: stmmac: Hold rtnl lock in suspend/resume callbacks")
Suggested-by: Bitan Biswas <bbiswas@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Thierry Reding 2019-10-02 16:49:46 +02:00 committed by David S. Miller
parent 53de429f4e
commit 134cc4cefa

View File

@ -4716,10 +4716,10 @@ int stmmac_suspend(struct device *dev)
if (!ndev || !netif_running(ndev))
return 0;
mutex_lock(&priv->lock);
phylink_mac_change(priv->phylink, false);
mutex_lock(&priv->lock);
netif_device_detach(ndev);
stmmac_stop_all_queues(priv);
@ -4733,9 +4733,11 @@ int stmmac_suspend(struct device *dev)
stmmac_pmt(priv, priv->hw, priv->wolopts);
priv->irq_wake = 1;
} else {
mutex_unlock(&priv->lock);
rtnl_lock();
phylink_stop(priv->phylink);
rtnl_unlock();
mutex_lock(&priv->lock);
stmmac_mac_set(priv, priv->ioaddr, false);
pinctrl_pm_select_sleep_state(priv->device);
@ -4827,6 +4829,8 @@ int stmmac_resume(struct device *dev)
stmmac_start_all_queues(priv);
mutex_unlock(&priv->lock);
if (!device_may_wakeup(priv->device)) {
rtnl_lock();
phylink_start(priv->phylink);
@ -4835,8 +4839,6 @@ int stmmac_resume(struct device *dev)
phylink_mac_change(priv->phylink, true);
mutex_unlock(&priv->lock);
return 0;
}
EXPORT_SYMBOL_GPL(stmmac_resume);