[PATCH 3.18 110/144] igb: Unpair the queues when changing the number of queues

[Greg Kroah-Hartman]

3.18-stable review patch.  If anyone has any objections, please let me know.

------------------

[ Upstream commit 37a5d163fb447b39f7960d0534de30e88ad395bb ]

By the commit 72ddef0506da ("igb: Fix oops caused by missing queue
pairing"), the IGB_FLAG_QUEUE_PAIRS flag can now be set when changing the
number of queues by "ethtool -L", but it is never cleared unless the igb
driver is reloaded.
This patch clears it if queue pairing becomes unnecessary as a result of
"ethtool -L".

Signed-off-by: Shota Suzuki <suzuki_shota_t3@xxxxxxxxxxxxx>
Tested-by: Aaron Brown <aaron.f.brown@xxxxxxxxx>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/net/ethernet/intel/igb/igb_main.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/net/ethernet/intel/igb/igb_main.c b/drivers/net/ethernet/intel/igb/igb_main.c
index 1ffad88e8a29..84049078c4f0 100644
--- a/drivers/net/ethernet/intel/igb/igb_main.c
+++ b/drivers/net/ethernet/intel/igb/igb_main.c
@@ -2941,6 +2941,8 @@ void igb_set_flag_queue_pairs(struct igb_adapter *adapter,
 		 */
 		if (adapter->rss_queues > (max_rss_queues / 2))
 			adapter->flags |= IGB_FLAG_QUEUE_PAIRS;
+		else
+			adapter->flags &= ~IGB_FLAG_QUEUE_PAIRS;
 		break;
 	}
 }
-- 
2.17.1