[PATCH net-next 10/11] net: Add warning if any lower device is still in adjacency list

David Ahern
2016-10-18T02:15:52Z

Lower list should be empty just like upper.

Signed-off-by: David Ahern <dsa-qUQiAmfTcIp+XZJcv9eMoEEOCMrvLtNR@public.gmane.org>
---
net/core/dev.c | 15 +++++++++++++++
1 file changed, 15 insertions(+)

diff --git a/net/core/dev.c b/net/core/dev.c
index a9fe14908b44..c6bbf310d407 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -5219,6 +5219,20 @@ struct net_device *netdev_master_upper_dev_get(struct net_device *dev)
}
EXPORT_SYMBOL(netdev_master_upper_dev_get);

+/**
+ * netdev_has_any_lower_dev - Check if device is linked to some device
+ * @dev: device
+ *
+ * Find out if a device is linked to a lower device and return true in case
+ * it is. The caller must hold the RTNL lock.
+ */
+static bool netdev_has_any_lower_dev(struct net_device *dev)
+{
+ ASSERT_RTNL();
+
+ return !list_empty(&dev->adj_list.lower);
+}
+
void *netdev_adjacent_get_private(struct list_head *adj_list)
{
struct netdev_adjacent *adj;
@@ -6616,6 +6630,7 @@ static void rollback_registered_many(struct list_head *head)

/* Notifier chain MUST detach us all upper devices. */
WARN_ON(netdev_has_any_upper_dev(dev));
+ WARN_ON(netdev_has_any_lower_dev(dev));

/* Remove entries from kobject tree */
netdev_unregister_kobject(dev);