Hello,
      I was reading some tcpdump's of netdump traffic today, and I realized that all of the packets that go from the crashing machine to the netdump server have a zero checksum.  Looking at the code, it looks like netconsole/netdump use the function netpoll_send_udp to send out the packets.  However, in netdump_send_udp, the checksum is set to 0, and never seems to be computed.  Is this intentional, or just an oversight?  I would think that we would always want to compute the UDP checksum, but there might be something I am overlooking.  Incidentally, it seems like the only user of netpoll_send_udp is netconsole (and netdump in RedHat kernels).
     Assuming that this is just an oversight, attached is a simple patch to compute the UDP checksum in netpoll_send_udp.

Signed-off-by: Chris Lalancette <clalance@redhat.com>