[PATCH v2 3/3] nvme-fabrics: prevent overriding of existing host

[Christoph Hellwig]

> +
>  	list_for_each_entry(host, &nvmf_hosts, list) {
> +		if (!strcmp(host->nqn, hostnqn)) {
> +			if (uuid_equal(&host->id, id)) {
> +				// same hostnqn and hostid
> +				return host;
> +			} else {
> +				pr_err("found same hostnqn %s but different hostid %pUb\n",
> +				       hostnqn, id);
> +				return ERR_PTR(-EINVAL);
> +			}
> +		} else if (uuid_equal(&host->id, id)) {
> +			// same hostid but different hostnqn
> +			pr_err("found same hostid %pUb but different hostnqn %s\n",
> +			        id, hostnqn);
> +			return ERR_PTR(-EINVAL);
> +		}
>  	}

Please avoid the c++ style comments.  But If the code was structured
a little different, they might not even be beeded, i.e.

		bool same_hostnqn = !strcmp(host->nqn, hostnqn);
		bool same_hostid = uuid_equal(&host->id, id);

		if (same_hostnqn && same_hostid)
			return host;

		if (same_hostnqn) {
			pr_err("found same hostnqn %s but different hostid %pUb\n",
			       hostnqn, id);
			return ERR_PTR(-EINVAL);
		}
		if (same_hostid) {
			pr_err("found same hostid %pUb but different hostnqn %s\n",
		        	id, hostnqn);
			return ERR_PTR(-EINVAL);
		}