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| author | Gregory CLEMENT <gregory.clement@free-electrons.com> | 2016-03-12 18:44:17 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2016-04-20 15:45:13 +0900 |
| commit | 51775f3da4437095675329fe9bd23ca579197ff2 (patch) | |
| tree | 09bbb8ea740b15bc88bc4de50d249433722e3600 /drivers/net | |
| parent | 03cbd08593beff8d7d3e51c68079e4414e50fcca (diff) | |
| download | lwn-51775f3da4437095675329fe9bd23ca579197ff2.tar.gz lwn-51775f3da4437095675329fe9bd23ca579197ff2.zip | |
net: mvneta: Fix spinlock usage
[ Upstream commit 1c2722a975fdb8c90bc6ba8570b7fb62db4e2e9c ]
In the previous patch, the spinlock was not initialized. While it didn't
cause any trouble yet it could be a problem to use it uninitialized.
The most annoying part was the critical section protected by the spinlock
in mvneta_stop(). Some of the functions could sleep as pointed when
activated CONFIG_DEBUG_ATOMIC_SLEEP. Actually, in mvneta_stop() we only
need to protect the is_stopped flagged, indeed the code of the notifier
for CPU online is protected by the same spinlock, so when we get the
lock, the notifer work is done.
Reported-by: Patrick Uiterwijk <patrick@puiterwijk.org>
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/net')
| -rw-r--r-- | drivers/net/ethernet/marvell/mvneta.c | 11 |
1 files changed, 6 insertions, 5 deletions
diff --git a/drivers/net/ethernet/marvell/mvneta.c b/drivers/net/ethernet/marvell/mvneta.c index acb1c5b2bad3..2ee05cebea75 100644 --- a/drivers/net/ethernet/marvell/mvneta.c +++ b/drivers/net/ethernet/marvell/mvneta.c @@ -3070,17 +3070,17 @@ static int mvneta_stop(struct net_device *dev) struct mvneta_port *pp = netdev_priv(dev); /* Inform that we are stopping so we don't want to setup the - * driver for new CPUs in the notifiers + * driver for new CPUs in the notifiers. The code of the + * notifier for CPU online is protected by the same spinlock, + * so when we get the lock, the notifer work is done. */ spin_lock(&pp->lock); pp->is_stopped = true; + spin_unlock(&pp->lock); + mvneta_stop_dev(pp); mvneta_mdio_remove(pp); unregister_cpu_notifier(&pp->cpu_notifier); - /* Now that the notifier are unregistered, we can release le - * lock - */ - spin_unlock(&pp->lock); on_each_cpu(mvneta_percpu_disable, pp, true); free_percpu_irq(dev->irq, pp->ports); mvneta_cleanup_rxqs(pp); @@ -3612,6 +3612,7 @@ static int mvneta_probe(struct platform_device *pdev) dev->ethtool_ops = &mvneta_eth_tool_ops; pp = netdev_priv(dev); + spin_lock_init(&pp->lock); pp->phy_node = phy_node; pp->phy_interface = phy_mode; |