bnxt_re: Remove RTNL lock dependency in bnxt_re_query_port

When there is a NETDEV_UNREGISTER event, bnxt_re driver calls
ib_unregister_device() (RTNL lock held).
ib_unregister_device attempts to flush a worker queue scheduled by
ib_core and that queue might have a pending ib_query_port().
ib_query_port in turn calls bnxt_re_query_port(), which while querying the
link speed using ib_get_eth_speed(), tries to acquire the rtnl_lock() which
was already held by NETDEV_UNREGISTER.
Fixing the issue by removing the link speed query from bnxt_re_query_port()
Now the speed is queried post a successful ib_register_device or whenever
there is a NETDEV_CHANGE event.

Signed-off-by: Somnath Kotur <somnath.kotur@broadcom.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

1 files changed, 4 insertions, 0 deletions

diff --git a/drivers/infiniband/hw/bnxt_re/main.c b/drivers/infiniband/hw/bnxt_re/main.c
index 29c3d7e254af..e7450ea92aa9 100644
--- a/drivers/infiniband/hw/bnxt_re/main.c
+++ b/drivers/infiniband/hw/bnxt_re/main.c
@@ -1161,6 +1161,8 @@ static int bnxt_re_ib_reg(struct bnxt_re_dev *rdev)
 		}
 	}
 	set_bit(BNXT_RE_FLAG_IBDEV_REGISTERED, &rdev->flags);
+	ib_get_eth_speed(&rdev->ibdev, 1, &rdev->active_speed,
+			 &rdev->active_width);
 	bnxt_re_dispatch_event(&rdev->ibdev, NULL, 1, IB_EVENT_PORT_ACTIVE);
 	bnxt_re_dispatch_event(&rdev->ibdev, NULL, 1, IB_EVENT_GID_CHANGE);
 
@@ -1255,6 +1257,8 @@ static void bnxt_re_task(struct work_struct *work)
 		else if (netif_carrier_ok(rdev->netdev))
 			bnxt_re_dispatch_event(&rdev->ibdev, NULL, 1,
 					       IB_EVENT_PORT_ACTIVE);
+		ib_get_eth_speed(&rdev->ibdev, 1, &rdev->active_speed,
+				 &rdev->active_width);
 		break;
 	default:
 		break;