Calling netdev_queue_update_kobjects is allowed during device
unregistration since commit
5c56580b74e5 ("net: Adjust TX queue kobjects
if number of queues changes during unregister"). But this is solely to
allow queue unregistrations. Any path attempting to add new queues after
a device started its unregistration should be fixed.
This patch adds a warning to detect such illegal use.
Signed-off-by: Antoine Tenart <atenart@kernel.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
int i;
int error = 0;
+ /* Tx queue kobjects are allowed to be updated when a device is being
+ * unregistered, but solely to remove queues from qdiscs. Any path
+ * adding queues should be fixed.
+ */
+ WARN(dev->reg_state == NETREG_UNREGISTERING && new_num > old_num,
+ "New queues can't be registered after device unregistration.");
+
for (i = old_num; i < new_num; i++) {
error = netdev_queue_add_kobject(dev, i);
if (error) {