@@ -1455,13 +1455,15 @@ static ssize_t set_mode(struct device *d, struct device_attribute *attr,
struct net_device *dev = to_net_dev(d);
struct ipoib_dev_priv *priv = netdev_priv(dev);
+ if (!rtnl_trylock())
+ return restart_syscall();
+
/* flush paths if we switch modes so that connections are restarted */
if (IPOIB_CM_SUPPORTED(dev->dev_addr) && !strcmp(buf, "connected\n")) {
set_bit(IPOIB_FLAG_ADMIN_CM, &priv->flags);
ipoib_warn(priv, "enabling connected mode "
"will cause multicast packet drops\n");
- rtnl_lock();
dev->features &= ~(NETIF_F_IP_CSUM | NETIF_F_SG | NETIF_F_TSO);
rtnl_unlock();
priv->tx_wr.send_flags &= ~IB_SEND_IP_CSUM;
@@ -1473,7 +1475,6 @@ static ssize_t set_mode(struct device *d, struct device_attribute *attr,
if (!strcmp(buf, "datagram\n")) {
clear_bit(IPOIB_FLAG_ADMIN_CM, &priv->flags);
- rtnl_lock();
if (test_bit(IPOIB_FLAG_CSUM, &priv->flags)) {
dev->features |= NETIF_F_IP_CSUM | NETIF_F_SG;
if (priv->hca_caps & IB_DEVICE_UD_TSO)
@@ -1485,6 +1486,7 @@ static ssize_t set_mode(struct device *d, struct device_attribute *attr,
return count;
}
+ rtnl_unlock();
return -EINVAL;
}
@@ -61,7 +61,8 @@ int ipoib_vlan_add(struct net_device *pdev, unsigned short pkey)
ppriv = netdev_priv(pdev);
- rtnl_lock();
+ if (!rtnl_trylock())
+ return restart_syscall();
mutex_lock(&ppriv->vlan_mutex);
/*
@@ -167,7 +168,8 @@ int ipoib_vlan_delete(struct net_device *pdev, unsigned short pkey)
ppriv = netdev_priv(pdev);
- rtnl_lock();
+ if (!rtnl_trylock())
+ return restart_syscall();
mutex_lock(&ppriv->vlan_mutex);
list_for_each_entry_safe(priv, tpriv, &ppriv->child_intfs, list) {
if (priv->pkey == pkey) {
Network device sysfs files that grab the rtnl_lock unconditionally will deadlock if accessed when the network device is being unregistered. So use trylock and syscall_restart to avoid this deadlock. Signed-off-by: Eric W. Biederman <ebiederm@aristanetworks.com> --- drivers/infiniband/ulp/ipoib/ipoib_cm.c | 6 ++++-- drivers/infiniband/ulp/ipoib/ipoib_vlan.c | 6 ++++-- 2 files changed, 8 insertions(+), 4 deletions(-)