Commit 1b18f09d authored by Rick Lindsley's avatar Rick Lindsley Committed by David S. Miller
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ibmvnic: Properly dispose of all skbs during a failover. 



During a reset, there may have been transmits in flight that are no
longer valid and cannot be fulfilled.  Resetting and clearing the
queues is insufficient; each skb also needs to be explicitly freed
so that upper levels are not left waiting for confirmation of a
transmit that will never happen.  If this happens frequently enough,
the apparent backlog will cause TCP to begin "congestion control"
unnecessarily, culminating in permanently decreased throughput.

Fixes: d7c0ef36 ("ibmvnic: Free and re-allocate scrqs when tx/rx scrqs change")
Tested-by: default avatarNick Child <nnac123@linux.ibm.com>
Reviewed-by: default avatarBrian King <brking@linux.vnet.ibm.com>
Signed-off-by: default avatarRick Lindsley <ricklind@us.ibm.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent ea1c3b77

drivers/net/ethernet/ibm/ibmvnic.c

+9 −0
Original line number Diff line number Diff line
@@ -5981,6 +5981,15 @@ static int ibmvnic_reset_init(struct ibmvnic_adapter *adapter, bool reset) 
			release_sub_crqs(adapter, 0);

			rc = init_sub_crqs(adapter);

		} else {

			/* no need to reinitialize completely, but we do

			 * need to clean up transmits that were in flight

			 * when we processed the reset.  Failure to do so

			 * will confound the upper layer, usually TCP, by

			 * creating the illusion of transmits that are

			 * awaiting completion.

			 */

			clean_tx_pools(adapter);



			rc = reset_sub_crq_queues(adapter);

		}

	} else {