This is a note to let you know that I've just added the patch titled ibmvnic: Properly dispose of all skbs during a failover. to the 5.18-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: ibmvnic-properly-dispose-of-all-skbs-during-a-failov.patch and it can be found in the queue-5.18 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 65c56af6bcc95373b50345db2601be158054e6ef Author: Rick Lindsley <ricklind@xxxxxxxxxx> Date: Sat Jul 2 03:37:12 2022 -0700 ibmvnic: Properly dispose of all skbs during a failover. [ Upstream commit 1b18f09d31cfa7148df15a7d5c5e0e86f105f7d1 ] During a reset, there may have been transmits in flight that are no longer valid and cannot be fulfilled.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: d7c0ef36bde03 ("ibmvnic: Free and re-allocate scrqs when tx/rx scrqs change") Tested-by: Nick Child <nnac123@xxxxxxxxxxxxx> Reviewed-by: Brian King <brking@xxxxxxxxxxxxxxxxxx> Signed-off-by: Rick Lindsley <ricklind@xxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/net/ethernet/ibm/ibmvnic.c b/drivers/net/ethernet/ibm/ibmvnic.c index 5c5931dba51d..c4221f89ab18 100644 --- a/drivers/net/ethernet/ibm/ibmvnic.c +++ b/drivers/net/ethernet/ibm/ibmvnic.c @@ -5774,6 +5774,15 @@ 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 {