RDMA/srpt: Fix disabling device management

Avoid disabling device management for devices that don't support
Management datagrams (MADs) by checking if the "mad_agent" pointer is
initialized before calling ib_modify_port, also fix the error flow in
srpt_refresh_port() to disable device management if
ib_register_mad_agent() fail.

Fixes: 09f8a1486dca ("RDMA/srpt: Fix handling of SR-IOV and iWARP ports")
Link: https://lore.kernel.org/r/20200514114720.141139-1-kamalheib1@gmail.com
Signed-off-by: Kamal Heib <kamalheib1@gmail.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

diff --git a/drivers/infiniband/ulp/srpt/ib_srpt.c b/drivers/infiniband/ulp/srpt/ib_srpt.c
index 63056af5337c2ab7df2487d6156848e06643336a..a294630f2100390deb1d3ff2c1e6006365930e11 100644 (file)
--- a/drivers/infiniband/ulp/srpt/ib_srpt.c
+++ b/drivers/infiniband/ulp/srpt/ib_srpt.c
@@ -607,6 +607,11 @@ static int srpt_refresh_port(struct srpt_port *sport)
                               dev_name(&sport->sdev->device->dev), sport->port,
                               PTR_ERR(sport->mad_agent));
                        sport->mad_agent = NULL;
+                       memset(&port_modify, 0, sizeof(port_modify));
+                       port_modify.clr_port_cap_mask = IB_PORT_DEVICE_MGMT_SUP;
+                       ib_modify_port(sport->sdev->device, sport->port, 0,
+                                      &port_modify);
+
                }
        }
 
@@ -630,9 +635,8 @@ static void srpt_unregister_mad_agent(struct srpt_device *sdev)
        for (i = 1; i <= sdev->device->phys_port_cnt; i++) {
                sport = &sdev->port[i - 1];
                WARN_ON(sport->port != i);
-               if (ib_modify_port(sdev->device, i, 0, &port_modify) < 0)
-                       pr_err("disabling MAD processing failed.\n");
                if (sport->mad_agent) {
+                       ib_modify_port(sdev->device, i, 0, &port_modify);
                        ib_unregister_mad_agent(sport->mad_agent);
                        sport->mad_agent = NULL;
                }