From f39f0d1e1e93145a0e91d9a7a639c42fd037ecc3 Mon Sep 17 00:00:00 2001 From: Thomas Falcon Date: Tue, 14 Feb 2017 10:22:59 -0600 Subject: [PATCH] ibmvnic: Fix initial MTU settings In the current driver, the MTU is set to the maximum value capable for the backing device. This decision turned out to be a mistake as it led to confusion among users. The expected initial MTU value used for other IBM vNIC capable operating systems is 1500, with the maximum value (9000) reserved for when Jumbo frames are enabled. This patch sets the MTU to the default value for a net device. It also corrects a discrepancy between MTU values received from firmware, which includes the ethernet header length, and net device MTU values. Finally, it removes redundant min/max MTU assignments after device initialization. Signed-off-by: Thomas Falcon Signed-off-by: David S. Miller --- drivers/net/ethernet/ibm/ibmvnic.c | 12 +++++------- 1 file changed, 5 insertions(+), 7 deletions(-) diff --git a/drivers/net/ethernet/ibm/ibmvnic.c b/drivers/net/ethernet/ibm/ibmvnic.c index 752b0822b020..5b66b4fd1767 100644 --- a/drivers/net/ethernet/ibm/ibmvnic.c +++ b/drivers/net/ethernet/ibm/ibmvnic.c @@ -1497,7 +1497,7 @@ static void init_sub_crqs(struct ibmvnic_adapter *adapter, int retry) adapter->req_rx_queues = adapter->opt_rx_comp_queues; adapter->req_rx_add_queues = adapter->max_rx_add_queues; - adapter->req_mtu = adapter->max_mtu; + adapter->req_mtu = adapter->netdev->mtu + ETH_HLEN; } total_queues = adapter->req_tx_queues + adapter->req_rx_queues; @@ -2627,12 +2627,12 @@ static void handle_query_cap_rsp(union ibmvnic_crq *crq, break; case MIN_MTU: adapter->min_mtu = be64_to_cpu(crq->query_capability.number); - netdev->min_mtu = adapter->min_mtu; + netdev->min_mtu = adapter->min_mtu - ETH_HLEN; netdev_dbg(netdev, "min_mtu = %lld\n", adapter->min_mtu); break; case MAX_MTU: adapter->max_mtu = be64_to_cpu(crq->query_capability.number); - netdev->max_mtu = adapter->max_mtu; + netdev->max_mtu = adapter->max_mtu - ETH_HLEN; netdev_dbg(netdev, "max_mtu = %lld\n", adapter->max_mtu); break; case MAX_MULTICAST_FILTERS: @@ -3657,9 +3657,7 @@ static void handle_crq_init_rsp(struct work_struct *work) goto task_failed; netdev->real_num_tx_queues = adapter->req_tx_queues; - netdev->mtu = adapter->req_mtu; - netdev->min_mtu = adapter->min_mtu; - netdev->max_mtu = adapter->max_mtu; + netdev->mtu = adapter->req_mtu - ETH_HLEN; if (adapter->failover) { adapter->failover = false; @@ -3799,7 +3797,7 @@ static int ibmvnic_probe(struct vio_dev *dev, const struct vio_device_id *id) } netdev->real_num_tx_queues = adapter->req_tx_queues; - netdev->mtu = adapter->req_mtu; + netdev->mtu = adapter->req_mtu - ETH_HLEN; rc = register_netdev(netdev); if (rc) { -- 2.20.1