diff options
| author | Gregory CLEMENT <gregory.clement@free-electrons.com> | 2016-03-12 18:44:17 +0100 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2016-03-14 20:48:51 +0100 |
| commit | 1c2722a975fdb8c90bc6ba8570b7fb62db4e2e9c (patch) | |
| tree | 488a09415a2b84f82e3612d45694f292218197a5 /drivers/net | |
| parent | bridge: fix potential use-after-free when hook returns QUEUE or STOLEN verdict (diff) | |
| download | linux-1c2722a975fdb8c90bc6ba8570b7fb62db4e2e9c.tar.xz linux-1c2722a975fdb8c90bc6ba8570b7fb62db4e2e9c.zip | |
net: mvneta: Fix spinlock usage
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>
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 be92668faf3e..665eac2c2469 100644 --- a/drivers/net/ethernet/marvell/mvneta.c +++ b/drivers/net/ethernet/marvell/mvneta.c @@ -3480,17 +3480,17 @@ 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); @@ -4023,6 +4023,7 @@ 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; |