[PATCH 4.9 049/271] iwlwifi: mvm: fix A-MPDU reference assignment

[Greg Kroah-Hartman]

From: Johannes Berg <johannes.berg@xxxxxxxxx>

[ Upstream commit 1f7698abedeeb3fef3cbcf78e16f925df675a179 ]

The current code assigns the reference, and then goes to increment
it if the toggle bit has changed. That way, we get

Toggle  0  0  0  0  1  1  1  1
ID      1  1  1  1  1  2  2  2

Fix that by assigning the post-toggle ID to get

Toggle  0  0  0  0  1  1  1  1
ID      1  1  1  1  2  2  2  2

Reported-by: Danny Alexander <danny.alexander@xxxxxxxxx>
Signed-off-by: Johannes Berg <johannes.berg@xxxxxxxxx>
Fixes: fbe4112791b8 ("iwlwifi: mvm: update mpdu metadata API")
Signed-off-by: Luca Coelho <luciano.coelho@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/net/wireless/intel/iwlwifi/mvm/rxmq.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/rxmq.c b/drivers/net/wireless/intel/iwlwifi/mvm/rxmq.c
index c2bbc8c17beb9..bc06d87a0106c 100644
--- a/drivers/net/wireless/intel/iwlwifi/mvm/rxmq.c
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/rxmq.c
@@ -810,12 +810,12 @@ void iwl_mvm_rx_mpdu_mq(struct iwl_mvm *mvm, struct napi_struct *napi,
 		bool toggle_bit = phy_info & IWL_RX_MPDU_PHY_AMPDU_TOGGLE;
 
 		rx_status->flag |= RX_FLAG_AMPDU_DETAILS;
-		rx_status->ampdu_reference = mvm->ampdu_ref;
 		/* toggle is switched whenever new aggregation starts */
 		if (toggle_bit != mvm->ampdu_toggle) {
 			mvm->ampdu_ref++;
 			mvm->ampdu_toggle = toggle_bit;
 		}
+		rx_status->ampdu_reference = mvm->ampdu_ref;
 	}
 
 	rcu_read_lock();
-- 
2.20.1