【Question for srpt in kernel-4.14】

[oulijun <oulijun@huawei.com>]

Hi, Bart Van Assche & Doug Ledford
  I am targeting a problem about RoCE and SCSI over RDMA from srpt in kernel-4.14. When insmod srpt.ko and insmod hns-roce-hw-v2.ko, it will
report a warning in srpt_add_one:
  ib_srpt srpt_add_one(hns_0) failed.

  I am tracking the error from ib_cm_listen in srpt_add_one.I found it returned an error when doing server_id validation
the error code as follows:
  static int __ib_cm_listen(struct ib_cm_id *cm_id, __be64 service_id,
			  __be64 service_mask)
{
	struct cm_id_private *cm_id_priv, *cur_cm_id_priv;
	int ret = 0;

	service_mask = service_mask ? service_mask : ~cpu_to_be64(0);
	service_id &= service_mask;
	if ((service_id & IB_SERVICE_ID_AGN_MASK) == IB_CM_ASSIGN_SERVICE_ID &&
	    (service_id != IB_CM_ASSIGN_SERVICE_ID))
		return -EINVAL;
 	......
 }

static void srpt_add_one(struct ib_device *device)
{
	struct srpt_device *sdev;
	struct srpt_port *sport;
	int i;

	pr_debug("device = %p\n", device);

	sdev = kzalloc(sizeof(*sdev), GFP_KERNEL);
	if (!sdev)
		goto err;

	sdev->device = device;
	mutex_init(&sdev->sdev_mutex);

	sdev->pd = ib_alloc_pd(device, 0);
	if (IS_ERR(sdev->pd))
		goto free_dev;

	sdev->lkey = sdev->pd->local_dma_lkey;

	sdev->srq_size = min(srpt_srq_size, sdev->device->attrs.max_srq_wr);

	srpt_use_srq(sdev, sdev->port[0].port_attrib.use_srq);

	if (!srpt_service_guid)
		srpt_service_guid = be64_to_cpu(device->node_guid);

	sdev->cm_id = ib_create_cm_id(device, srpt_cm_handler, sdev);
	if (IS_ERR(sdev->cm_id))
		goto err_ring;

	/* print out target login information */
	pr_debug("Target login info: id_ext=%016llx,ioc_guid=%016llx,"
		 "pkey=ffff,service_id=%016llx\n", srpt_service_guid,
		 srpt_service_guid, srpt_service_guid);

	/*
	 * We do not have a consistent service_id (ie. also id_ext of target_id)
	 * to identify this target. We currently use the guid of the first HCA
	 * in the system as service_id; therefore, the target_id will change
	 * if this HCA is gone bad and replaced by different HCA
	 */
	if (ib_cm_listen(sdev->cm_id, cpu_to_be64(srpt_service_guid), 0))
		goto err_cm;

	......
}

However, I check the srpt_service_guid is obtained by device->node_guid. I think that the compute algorithm is ok for device->node_guid.
In addition, I analyzed a patch in kernel-4.17(IB/srpt: Add RDMA/CM support). As a result, I can understand that the previous srpt is not supported by RDMA/CM?
So, all RoCE will failed when use kernel-4.14 version to run srpt.ko?

Thanks
Lijun Ou