[PATCH 1/2] net: stmmac: Fix possible deadlock when disabling EEE support

From: Jon Hunter
Date: Wed Jun 26 2019 - 06:23:44 EST


When stmmac_eee_init() is called to disable EEE support, then the timer
for EEE support is stopped and we return from the function. Prior to
stopping the timer, a mutex was acquired but in this case it is never
released and so could cause a deadlock. Fix this by releasing the mutex
prior to returning from stmmax_eee_init() when stopping the EEE timer.

Fixes: 74371272f97f ("net: stmmac: Convert to phylink and remove phylib logic")
Signed-off-by: Jon Hunter <jonathanh@xxxxxxxxxx>
---
drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index b628c697cee9..6c6c6ec3c781 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -402,6 +402,7 @@ bool stmmac_eee_init(struct stmmac_priv *priv)
netdev_dbg(priv->dev, "disable EEE\n");
del_timer_sync(&priv->eee_ctrl_timer);
stmmac_set_eee_timer(priv, priv->hw, 0, tx_lpi_timer);
+ mutex_unlock(&priv->lock);
return false;
}

--
1.9.1