From: stephen hemminger <[email protected]> 3.12-stable review patch. If anyone has any objections, please let me know.
=============== [ Upstream commit a50af86dd49ee1851d1ccf06dd0019c05b95e297 ] Hyper-V (and Azure) support using NVGRE which requires some extra space for encapsulation headers. Because of this the largest allowed TSO packet is reduced. For older releases, hard code a fixed reduced value. For next release, there is a better solution which uses result of host offload negotiation. Signed-off-by: Stephen Hemminger <[email protected]> Signed-off-by: David S. Miller <[email protected]> Signed-off-by: Jiri Slaby <[email protected]> --- drivers/net/hyperv/netvsc_drv.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/net/hyperv/netvsc_drv.c b/drivers/net/hyperv/netvsc_drv.c index 616b4e1dd44c..eb6d0d8a3e06 100644 --- a/drivers/net/hyperv/netvsc_drv.c +++ b/drivers/net/hyperv/netvsc_drv.c @@ -48,6 +48,9 @@ struct net_device_context { struct work_struct work; }; +/* Restrict GSO size to account for NVGRE */ +#define NETVSC_GSO_MAX_SIZE 62768 + #define RING_SIZE_MIN 64 static int ring_size = 128; module_param(ring_size, int, S_IRUGO); @@ -435,6 +438,7 @@ static int netvsc_probe(struct hv_device *dev, SET_ETHTOOL_OPS(net, ðtool_ops); SET_NETDEV_DEV(net, &dev->device); + netif_set_gso_max_size(net, NETVSC_GSO_MAX_SIZE); ret = register_netdev(net); if (ret != 0) { -- 2.11.0

