If the host uses packet encapsulation feature, the MTU may be reduced by the host due to headroom reservation for encapsulation. This patch handles this new MTU value. Signed-off-by: Haiyang Zhang <haiyangz@xxxxxxxxxxxxx> --- drivers/net/hyperv/netvsc.c | 3 ++- drivers/net/hyperv/netvsc_drv.c | 4 ++-- drivers/net/hyperv/rndis_filter.c | 9 +++++++++ 3 files changed, 13 insertions(+), 3 deletions(-) diff --git a/drivers/net/hyperv/netvsc.c b/drivers/net/hyperv/netvsc.c index 7d76c95..6b46311 100644 --- a/drivers/net/hyperv/netvsc.c +++ b/drivers/net/hyperv/netvsc.c @@ -440,7 +440,8 @@ static int negotiate_nvsp_ver(struct hv_device *device, /* NVSPv2 only: Send NDIS config */ memset(init_packet, 0, sizeof(struct nvsp_message)); init_packet->hdr.msg_type = NVSP_MSG2_TYPE_SEND_NDIS_CONFIG; - init_packet->msg.v2_msg.send_ndis_config.mtu = net_device->ndev->mtu; + init_packet->msg.v2_msg.send_ndis_config.mtu = net_device->ndev->mtu + + ETH_HLEN; init_packet->msg.v2_msg.send_ndis_config.capability.ieee8021q = 1; ret = vmbus_sendpacket(device->channel, init_packet, diff --git a/drivers/net/hyperv/netvsc_drv.c b/drivers/net/hyperv/netvsc_drv.c index 3295e4e..b689f96 100644 --- a/drivers/net/hyperv/netvsc_drv.c +++ b/drivers/net/hyperv/netvsc_drv.c @@ -699,9 +699,9 @@ static int netvsc_change_mtu(struct net_device *ndev, int mtu) return -ENODEV; if (nvdev->nvsp_version >= NVSP_PROTOCOL_VERSION_2) - limit = NETVSC_MTU; + limit = NETVSC_MTU - ETH_HLEN; - if (mtu < 68 || mtu > limit) + if (mtu < ETH_DATA_LEN || mtu > limit) return -EINVAL; nvdev->start_remove = true; diff --git a/drivers/net/hyperv/rndis_filter.c b/drivers/net/hyperv/rndis_filter.c index ccce6f2..7b2c5d1 100644 --- a/drivers/net/hyperv/rndis_filter.c +++ b/drivers/net/hyperv/rndis_filter.c @@ -998,6 +998,7 @@ int rndis_filter_device_add(struct hv_device *dev, int t; struct ndis_recv_scale_cap rsscap; u32 rsscap_size = sizeof(struct ndis_recv_scale_cap); + u32 mtu, size; rndis_device = get_rndis_device(); if (!rndis_device) @@ -1029,6 +1030,14 @@ int rndis_filter_device_add(struct hv_device *dev, return ret; } + /* Get the MTU from the host */ + size = sizeof(u32); + ret = rndis_filter_query_device(rndis_device, + RNDIS_OID_GEN_MAXIMUM_FRAME_SIZE, + &mtu, &size); + if (ret == 0 && size == sizeof(u32)) + net_device->ndev->mtu = mtu; + /* Get the mac address */ ret = rndis_filter_query_device_mac(rndis_device); if (ret != 0) { -- 1.7.1 _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel