From: Sukadev Bhattiprolu sukadev@linux.ibm.com
[ Upstream commit 8878e46fcfd46b19964bd90e13b25dd94cbfc9be ]
If adapter's resetting bit is on, discard the packet but don't stop the transmit queue - instead leave that to the reset code. With this change, it is possible that we may get several calls to ibmvnic_xmit() that simply discard packets and return.
But if we stop the queue here, we might end up doing so just after __ibmvnic_open() started the queues (during a hard/soft reset) and before the ->resetting bit was cleared. If that happens, there will be no one to restart queue and transmissions will be blocked indefinitely.
This can cause a TIMEOUT reset and with auto priority failover enabled, an unnecessary FAILOVER reset to less favored backing device and then a FAILOVER back to the most favored backing device. If we hit the window repeatedly, we can get stuck in a loop of TIMEOUT, FAILOVER, FAILOVER resets leaving the adapter unusable for extended periods of time.
Fixes: 7f5b030830fe ("ibmvnic: Free skb's in cases of failure in transmit") Reported-by: Abdul Haleem abdhalee@in.ibm.com Reported-by: Vaishnavi Bhat vaish123@in.ibm.com Signed-off-by: Sukadev Bhattiprolu sukadev@linux.ibm.com Reviewed-by: Dany Madden drt@linux.ibm.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/ethernet/ibm/ibmvnic.c | 2 -- 1 file changed, 2 deletions(-)
diff --git a/drivers/net/ethernet/ibm/ibmvnic.c b/drivers/net/ethernet/ibm/ibmvnic.c index cfe7229593ead..059eaa13e2c6d 100644 --- a/drivers/net/ethernet/ibm/ibmvnic.c +++ b/drivers/net/ethernet/ibm/ibmvnic.c @@ -1462,8 +1462,6 @@ static netdev_tx_t ibmvnic_xmit(struct sk_buff *skb, struct net_device *netdev) netdev_tx_t ret = NETDEV_TX_OK;
if (test_bit(0, &adapter->resetting)) { - if (!netif_subqueue_stopped(netdev, skb)) - netif_stop_subqueue(netdev, queue_num); dev_kfree_skb_any(skb);
tx_send_failed++;