From mboxrd@z Thu Jan 1 00:00:00 1970 From: Vladimir Zapolskiy Subject: [PATCH v2 02/14] sh_eth: fix invalid context bug while changing link options by ethtool Date: Wed, 4 Jul 2018 11:12:40 +0300 Message-ID: <20180704081245.7395-3-vladimir_zapolskiy@mentor.com> References: <20180704081245.7395-1-vladimir_zapolskiy@mentor.com> Mime-Version: 1.0 Content-Type: text/plain Cc: Andrew Lunn , Geert Uytterhoeven , , To: Sergei Shtylyov , "David S . Miller" Return-path: Received: from relay1.mentorg.com ([192.94.38.131]:42613 "EHLO relay1.mentorg.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932535AbeGDINF (ORCPT ); Wed, 4 Jul 2018 04:13:05 -0400 In-Reply-To: <20180704081245.7395-1-vladimir_zapolskiy@mentor.com> Sender: netdev-owner@vger.kernel.org List-ID: 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 --- drivers/net/ethernet/renesas/sh_eth.c | 49 ++++++++------------------- 1 file changed, 15 insertions(+), 34 deletions(-) diff --git a/drivers/net/ethernet/renesas/sh_eth.c b/drivers/net/ethernet/renesas/sh_eth.c index e8aca46bb925..8e429e865552 100644 --- a/drivers/net/ethernet/renesas/sh_eth.c +++ b/drivers/net/ethernet/renesas/sh_eth.c @@ -1927,8 +1927,15 @@ static void sh_eth_adjust_link(struct net_device *ndev) { 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; @@ -1947,18 +1954,21 @@ static void sh_eth_adjust_link(struct net_device *ndev) 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); } @@ -2049,39 +2059,10 @@ static int sh_eth_get_link_ksettings(struct net_device *ndev, 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 -- 2.17.1