ibmvnic: fix rx buffer tracking and index management in replenish_rx_pool partial success

Dwip N. Banerjee · davem330 · commit c2af62256e8d · 2020-12-09T19:06:10.000-08:00
We observed that in the error case for batched send_subcrq_indirect() the driver does not account for the partial success case. This caused Linux to crash when free_map and pool index are inconsistent. Driver needs to update the rx pools "available" count when some batched sends worked but an error was encountered as part of the whole operation. Also track replenish_add_buff_failure for statistic purposes. Fixes: 4f0b681 ("ibmvnic: Introduce batched RX buffer descriptor transmission") Signed-off-by: Dwip N. Banerjee <dnbanerg@us.ibm.com> Reviewed-by: Dany Madden <drt@linux.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ethernet/ibm/ibmvnic.c b/drivers/net/ethernet/ibm/ibmvnic.c
@@ -398,6 +398,8 @@ static void replenish_rx_pool(struct ibmvnic_adapter *adapter,
 		dev_kfree_skb_any(pool->rx_buff[index].skb);
 		pool->rx_buff[index].skb = NULL;
 	}
+	adapter->replenish_add_buff_failure += ind_bufp->index;
+	atomic_add(buffers_added, &pool->available);
 	ind_bufp->index = 0;
 	if (lpar_rc == H_CLOSED || adapter->failover_pending) {
 		/* Disable buffer pool replenishment and report carrier off if

Original file line number	Diff line number	Diff line change
`@@ -398,6 +398,8 @@ static void replenish_rx_pool(struct ibmvnic_adapter *adapter,`
`398`	`398`	`dev_kfree_skb_any(pool->rx_buff[index].skb);`
`399`	`399`	`pool->rx_buff[index].skb = NULL;`
`400`	`400`	`}`
	`401`	`+ adapter->replenish_add_buff_failure += ind_bufp->index;`
	`402`	`+ atomic_add(buffers_added, &pool->available);`
`401`	`403`	`ind_bufp->index = 0;`
`402`	`404`	`if (lpar_rc == H_CLOSED \|\| adapter->failover_pending) {`
`403`	`405`	`/* Disable buffer pool replenishment and report carrier off if`