4.17-stable review patch. If anyone has any objections, please let me know.
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From: Vladimir Zapolskiy vladimir_zapolskiy@mentor.com
[ Upstream commit 5cb3f52a11e18628fc4bee76dd14b1f0b76349de ]
The change fixes sleep in atomic context bug, which is encountered every time when link settings are changed by ethtool.
Since commit 35b5f6b1a82b ("PHYLIB: Locking fixes for PHY I/O potentially sleeping") phy_start_aneg() function utilizes a mutex to serialize changes to phy state, however that helper function is called in atomic context under a grabbed spinlock, because phy_start_aneg() is called by phy_ethtool_ksettings_set() and by replaced phy_ethtool_sset() helpers from phylib.
Now duplex mode setting is enforced in sh_eth_adjust_link() only, also now RX/TX is disabled when link is put down or modifications to E-MAC registers ECMR and GECMR are expected for both cases of checked and ignored link status pin state from E-MAC interrupt handler.
For reference the change is a partial rework of commit 1e1b812bbe10 ("sh_eth: fix handling of no LINK signal").
Fixes: dc19e4e5e02f ("sh: sh_eth: Add support ethtool") Signed-off-by: Vladimir Zapolskiy vladimir_zapolskiy@mentor.com Reviewed-by: Sergei Shtylyov sergei.shtylyov@cogentembedded.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/net/ethernet/renesas/sh_eth.c | 49 ++++++++++------------------------ 1 file changed, 15 insertions(+), 34 deletions(-)
--- a/drivers/net/ethernet/renesas/sh_eth.c +++ b/drivers/net/ethernet/renesas/sh_eth.c @@ -1855,8 +1855,15 @@ static void sh_eth_adjust_link(struct ne { struct sh_eth_private *mdp = netdev_priv(ndev); struct phy_device *phydev = ndev->phydev; + unsigned long flags; int new_state = 0;
+ spin_lock_irqsave(&mdp->lock, flags); + + /* Disable TX and RX right over here, if E-MAC change is ignored */ + if (mdp->cd->no_psr || mdp->no_ether_link) + sh_eth_rcv_snd_disable(ndev); + if (phydev->link) { if (phydev->duplex != mdp->duplex) { new_state = 1; @@ -1875,18 +1882,21 @@ static void sh_eth_adjust_link(struct ne sh_eth_modify(ndev, ECMR, ECMR_TXF, 0); new_state = 1; mdp->link = phydev->link; - if (mdp->cd->no_psr || mdp->no_ether_link) - sh_eth_rcv_snd_enable(ndev); } } else if (mdp->link) { new_state = 1; mdp->link = 0; mdp->speed = 0; mdp->duplex = -1; - if (mdp->cd->no_psr || mdp->no_ether_link) - sh_eth_rcv_snd_disable(ndev); }
+ /* Enable TX and RX right over here, if E-MAC change is ignored */ + if ((mdp->cd->no_psr || mdp->no_ether_link) && phydev->link) + sh_eth_rcv_snd_enable(ndev); + + mmiowb(); + spin_unlock_irqrestore(&mdp->lock, flags); + if (new_state && netif_msg_link(mdp)) phy_print_status(phydev); } @@ -1977,39 +1987,10 @@ static int sh_eth_get_link_ksettings(str static int sh_eth_set_link_ksettings(struct net_device *ndev, const struct ethtool_link_ksettings *cmd) { - struct sh_eth_private *mdp = netdev_priv(ndev); - unsigned long flags; - int ret; - if (!ndev->phydev) return -ENODEV;
- spin_lock_irqsave(&mdp->lock, flags); - - /* disable tx and rx */ - sh_eth_rcv_snd_disable(ndev); - - ret = phy_ethtool_ksettings_set(ndev->phydev, cmd); - if (ret) - goto error_exit; - - if (cmd->base.duplex == DUPLEX_FULL) - mdp->duplex = 1; - else - mdp->duplex = 0; - - if (mdp->cd->set_duplex) - mdp->cd->set_duplex(ndev); - -error_exit: - mdelay(1); - - /* enable tx and rx */ - sh_eth_rcv_snd_enable(ndev); - - spin_unlock_irqrestore(&mdp->lock, flags); - - return ret; + return phy_ethtool_ksettings_set(ndev->phydev, cmd); }
/* If it is ever necessary to increase SH_ETH_REG_DUMP_MAX_REGS, the