sh_eth: fix invalid context bug while calling auto-negotiation by ethtool

[ Upstream commit 53a710b5044d8475faa6813000b6dd659400ef7b ]

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 the helper function is
called in atomic context.

The bug can be reproduced by running "ethtool -r" command, the bug
is reported if CONFIG_DEBUG_ATOMIC_SLEEP build option is enabled.

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>

diff --git a/drivers/net/ethernet/renesas/sh_eth.c b/drivers/net/ethernet/renesas/sh_eth.c
index 38080e95a82dccc6286a0cd40829be35ac9612ee..22adaa169ddd0896be17e6304252879600ba29d8 100644 (file)
--- a/drivers/net/ethernet/renesas/sh_eth.c
+++ b/drivers/net/ethernet/renesas/sh_eth.c
@@ -2156,18 +2156,10 @@ static void sh_eth_get_regs(struct net_device *ndev, struct ethtool_regs *regs,
 
 static int sh_eth_nway_reset(struct net_device *ndev)
 {
-       struct sh_eth_private *mdp = netdev_priv(ndev);
-       unsigned long flags;
-       int ret;
-
        if (!ndev->phydev)
                return -ENODEV;
 
-       spin_lock_irqsave(&mdp->lock, flags);
-       ret = phy_start_aneg(ndev->phydev);
-       spin_unlock_irqrestore(&mdp->lock, flags);
-
-       return ret;
+       return phy_start_aneg(ndev->phydev);
 }
 
 static u32 sh_eth_get_msglevel(struct net_device *ndev)