Re: [PATCH v2 net-next 6/9] psp: Add new netlink cmd for dev-assoc and dev-disassoc

[Daniel Zahka <daniel.zahka@gmail.com>]

On 3/3/26 7:00 PM, Wei Wang wrote:
> +int psp_nl_dev_disassoc_doit(struct sk_buff *skb, struct genl_info *info)
> +{
> +	struct psp_assoc_dev *entry, *found = NULL;
> +	struct psp_dev *psd = info->user_ptr[0];
> +	u32 assoc_ifindex;
> +	struct sk_buff *rsp;
> +	struct net *net;
> +	int nsid;
> +
> +	if (GENL_REQ_ATTR_CHECK(info, PSP_A_DEV_IFINDEX) ||
> +	    GENL_REQ_ATTR_CHECK(info, PSP_A_DEV_NSID))
> +		return -EINVAL;
> +
> +	nsid = nla_get_s32(info->attrs[PSP_A_DEV_NSID]);
> +	net = get_net_ns_by_id(genl_info_net(info), nsid);
> +	if (!net) {
> +		NL_SET_BAD_ATTR(info->extack, info->attrs[PSP_A_DEV_NSID]);
> +		return -EINVAL;
> +	}
> +
> +	assoc_ifindex = nla_get_u32(info->attrs[PSP_A_DEV_IFINDEX]);
> +
> +	/* Search the association list by ifindex and netns */
> +	list_for_each_entry(entry, &psd->assoc_dev_list, dev_list) {
> +		if (entry->assoc_dev->ifindex == assoc_ifindex &&
> +		    dev_net(entry->assoc_dev) == net) {
> +			found = entry;
> +			break;
> +		}
> +	}
> +
> +	if (!found) {
> +		put_net(net);
> +		NL_SET_BAD_ATTR(info->extack, info->attrs[PSP_A_DEV_IFINDEX]);
> +		return -ENODEV;
> +	}
> +
> +	rsp = psp_nl_reply_new(info);
> +	if (!rsp) {
> +		put_net(net);
> +		return -ENOMEM;
> +	}
> +
> +	/* Remove from the association list */
> +	list_del(&found->dev_list);
> +	rcu_assign_pointer(found->assoc_dev->psp_dev, NULL);
> +	netdev_put(found->assoc_dev, &found->dev_tracker);
> +	kfree(found);

in the case where found was the last associated device in its netns in 
psd->assoc_dev_list, listeners in that netns will not receive any 
notification that a psp device has gone away.

> +
> +	put_net(net);
> +
> +	psp_nl_notify_dev(psd, PSP_CMD_DEV_CHANGE_NTF);