From: Jon Hunter Date: Wed, 26 Jun 2019 10:23:22 +0000 (+0100) Subject: net: stmmac: Fix crash observed if PHY does not support EEE X-Git-Tag: v5.4-rc1~616^2~142 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=177d935a13703eb809049c97c31a1e4d80b4cfbb;p=platform%2Fkernel%2Flinux-rpi.git net: stmmac: Fix crash observed if PHY does not support EEE If the PHY does not support EEE mode, then a crash is observed when the ethernet interface is enabled. The crash occurs, because if the PHY does not support EEE, then although the EEE timer is never configured, it is still marked as enabled and so the stmmac ethernet driver is still trying to update the timer by calling mod_timer(). This triggers a BUG() in the mod_timer() because we are trying to update a timer when there is no callback function set because timer_setup() was never called for this timer. The problem is caused because we return true from the function stmmac_eee_init(), marking the EEE timer as enabled, even when we have not configured the EEE timer. Fix this by ensuring that we return false if the PHY does not support EEE and hence, 'eee_active' is not set. Fixes: 74371272f97f ("net: stmmac: Convert to phylink and remove phylib logic") Signed-off-by: Jon Hunter Tested-by: Thierry Reding Signed-off-by: David S. Miller --- diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c index df9976c..ee4f1e2 100644 --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c @@ -398,10 +398,12 @@ bool stmmac_eee_init(struct stmmac_priv *priv) mutex_lock(&priv->lock); /* Check if it needs to be deactivated */ - if (!priv->eee_active && priv->eee_enabled) { - 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); + if (!priv->eee_active) { + if (priv->eee_enabled) { + 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; }