[net] e1000: Prevent reset task killing itself.

[Jeff Kirsher <jeffrey.t.kirsher@intel.com>]

From: Tushar Dave <tushar.n.dave@intel.com>

Killing reset task while adapter is resetting causes deadlock.
Only kill reset task if adapter is not resetting.
Ref bug #43132 on bugzilla.kernel.org

CC: stable@vger.kernel.org
Signed-off-by: Tushar Dave <tushar.n.dave@intel.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
---

@stable - this patch is applicable back to 3.1 kernels

---
 drivers/net/ethernet/intel/e1000/e1000_main.c |    6 +++++-
 1 files changed, 5 insertions(+), 1 deletions(-)

diff --git a/drivers/net/ethernet/intel/e1000/e1000_main.c b/drivers/net/ethernet/intel/e1000/e1000_main.c
index 37caa88..8d8908d 100644
--- a/drivers/net/ethernet/intel/e1000/e1000_main.c
+++ b/drivers/net/ethernet/intel/e1000/e1000_main.c
@@ -493,7 +493,11 @@ out:
 static void e1000_down_and_stop(struct e1000_adapter *adapter)
 {
 	set_bit(__E1000_DOWN, &adapter->flags);
-	cancel_work_sync(&adapter->reset_task);
+
+	/* Only kill reset task if adapter is not resetting */
+	if (!test_bit(__E1000_RESETTING, &adapter->flags))
+		cancel_work_sync(&adapter->reset_task);
+
 	cancel_delayed_work_sync(&adapter->watchdog_task);
 	cancel_delayed_work_sync(&adapter->phy_info_task);
 	cancel_delayed_work_sync(&adapter->fifo_stall_task);
-- 
1.7.7.6