[ofa-general] [RFC PATCH 4/4] rdma/cma: implement RDMA_ALIGN_WITH_NETDEVICE ha mode

[Roland Dreier]

 > Use netevent notification for sensing that a change has happened in the IP stack,
 > then scan the rdma-cm IDs list to see if there is an ID that is "misaligned"
 > in that respect with the IP stack, and disconnect it, in case this is what the
 > user asked to when setting an ha mode for the ID.

this seems like a strange "HA" feature -- to disconnect connections that
otherwise would continue operating.  What is the use case/use scenario?

 > +	list_for_each_entry(cma_dev, &dev_list, list)
 > +		list_for_each_entry(id_priv, &cma_dev->id_list, list) {
 > +			dev_addr = &id_priv->id.route.addr.dev_addr;
 > +			if (!memcmp(dev_addr->src_netdev_name, ndev->name, IFNAMSIZ) &&
 > +				memcmp(dev_addr->src_dev_addr, ndev->dev_addr, ndev->addr_len))
 > +					if (id_priv->ha_mode == RDMA_ALIGN_WITH_NETDEVICE)
 > +						schedule_work(&id_priv->ha_work);
 > +		}

This looks horribly racy/incorrect against RDMA device removal, CMA ID
destruction and netdev renaming.

 - R.