[net] ixgbe: fix possible deadlock in ixgbe_service_task()

[Jeff Kirsher]

From: Taehee Yoo <ap420...@gmail.com>

ixgbe_service_task() calls unregister_netdev() under rtnl_lock().
But unregister_netdev() internally calls rtnl_lock().
So deadlock would occur.

Fixes: 59dd45d550c5 ("ixgbe: firmware recovery mode")
Signed-off-by: Taehee Yoo <ap420...@gmail.com>
Tested-by: Andrew Bowers <andrewx.bow...@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirs...@intel.com>
---
 drivers/net/ethernet/intel/ixgbe/ixgbe_main.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c 
b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
index cbaf712d6529..3386e752e458 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
@@ -7898,9 +7898,7 @@ static void ixgbe_service_task(struct work_struct *work)
        }
        if (ixgbe_check_fw_error(adapter)) {
                if (!test_bit(__IXGBE_DOWN, &adapter->state)) {
-                       rtnl_lock();
                        unregister_netdev(adapter->netdev);
-                       rtnl_unlock();
                }
                ixgbe_service_event_complete(adapter);
                return;
-- 
2.21.0