Re: [PATCH net-next,v2] hyperv: Add handling of IP header with option field in netvsc_set_hash()

From: Haiyang Zhang <haiyangz@microsoft.com>
Date: Tue, 14 Oct 2014 15:16:28 -0700

In case that the IP header has optional field at the end, this patch will
get the port numbers after that field, and compute the hash.

Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
Reviewed-by: K. Y. Srinivasan <kys@microsoft.com>

Instead of adding hack after hack after hack to your internal header
parser, just use the generic flow dissector we already have in the
kernel to fetch out the values you need.

__skb_flow_get_ports() etc.